Changing the Party Sued

Changing the Party Sued

Rule 15(c)(1)(C) governs an amendment that changes the party or the naming of the party against whom a claim is asserted, and it demands more than the same-transaction test alone. The amendment must satisfy Rule 15(c)(1)(B), and within the period provided by Rule 4(m) for serving the summons and complaint, the party to be brought in must meet two further conditions.¹ It must have received such notice of the action that it will not be prejudiced in defending on the merits,² and it must have known or should have known that the action would have been brought against it but for a mistake concerning the proper party’s identity.³ One clock, the service period, measures both showings.

The extra layers reflect what relation back protects. A litigant who has been told of a lawsuit about a transaction has received all the protection that statutes of limitation are designed to afford, so an amendment resting on the facts the litigant learned at the outset can relate back even though limitations has run.⁴ On that premise, a counterclaim first pleaded in an amended pleading some eight years after the underlying events relates back to the original filing, even though it would be barred if sued upon separately.⁵ The same premise explains why adequate notice of the occurrence is the most important factor when a claim is added against a party already in the case. A complaint charging a physician with negligence in performing an amniocentesis gave that physician adequate notice of a later informed-consent claim that also concerned her behavior with respect to the procedure.⁶

A new party stands differently. The original complaint, aimed at someone else, told it nothing, and it may have believed that the limitations period passed in its favor. The rule therefore asks what the new party learned, how soon, and whether what it learned showed that the plaintiff had simply erred.

A teaching example shows the pattern. Surgeon Kevorkean performs a stomach tuck on Sam Suma. Afterward Suma develops a continuous pain in his side, Kevorkean dismisses it as a normal recovery symptom, and Suma asks Dr. Booker for a second opinion. Booker orders an x-ray, which shows that a small surgical clamp was left inside Suma, and Suma promptly sues Kevorkean for negligence in leaving the clamp.⁷

The inquiry runs in a fixed order. Because (C) incorporates (B), the claim must first arise out of the conduct, transaction, or occurrence set forth in the original pleading, and courts look to the operational facts in the original complaint to see whether the defendant was put on notice of the claim.⁸ Only an amendment that passes that test reaches the notice and mistake questions, and the service period frames both.

The Rule 4(m) Window

The service period, not the limitations period, is the clock. Within “the period provided by Rule 4(m) for serving the summons and complaint,” the new party must have received notice of the action and must have known or should have known of the mistake.⁹ The reason appears when you ask what a timely filing tells the original defendant. A plaintiff who files before limitations expires has sued in time, yet the defendant may not know it, because Rule 4(m) gives the plaintiff 90 days after filing to find the defendant and serve the papers.¹⁰ The drafters of Rule 15(c)(1)(C) concluded that an amendment adding a new defendant should relate back if the new defendant receives notice within that same, slightly longer period, so that she learns of the suit within the time she would have had as the original defendant.¹¹

The rule once used a different clock. In Schiavone v. Fortune, the plaintiffs sued “Fortune,” and the complaints sent to Time, Incorporated’s agent carried only that name. The corrected complaints, naming “Fortune, also known as Time, Incorporated,” were held barred, because, as the Supreme Court put it, “the linchpin is notice, and notice within the limitations period.”¹² The dissent saw the flaw. Time would have known nothing different on May 23, 1983 had the complaints referred to “Fortune, also known as Time, Incorporated,” yet the first complaints would have been completely timely and the second completely barred.¹³ The 1991 amendment to Rule 15(c), which took effect on December 1, 1991, was expressly designed to change the result in Schiavone, as the First Circuit recognized in Freund v. Fleetwood Enterprises, Inc.¹⁴

The amended window does real work. In Worthington v. Wilson, the original complaint, which named “unknown named police officers,” was filed on February 25, 1991, so the window closed on June 25, 1991. Defense counsel conceded that the officers knew of the action within that period, and the district court found that an amendment arising from the same conduct would be timely under the amended rule, because the officers received notice within 120 days of the original filing.¹⁵ Timely notice did not end the matter. Worthington is among the Seventh Circuit decisions holding that substituting real names for “unknown” defendants does not satisfy the mistake requirement,¹⁶ so meeting the window is necessary but not sufficient.

The count itself needs care. Several decisions discussed here say 120 days, the default service period when they were decided, and Krupski v. Costa Crociere S.p.A. likewise described the Rule 4(m) period as ordinarily 120 days from the filing of the complaint.¹⁷ The current period is 90 days, so a problem today should be counted from filing with 90.¹⁸ Because the rule points to “the period provided by Rule 4(m),” the window follows whatever service period applies in the case.¹⁹

Timing is often the least contested element when the new party is served promptly. In Leonard v. Parry, the First Circuit found the same-transaction requirement clearly satisfied and timely notice conceded, because the later-named driver had been served within the 120-day default period.²⁰

The window tests the new party’s information and sets no deadline for the plaintiff. The Krupski Court rejected the suggestion that Rule 15(c) requires a plaintiff to move to amend, or to file and serve an amended complaint, within the Rule 4(m) period. The clause asks only whether the prospective defendant received sufficient notice within that period, and the notice need not be formal.²¹ Krupski sought leave to add the proper defendant 133 days after filing and filed the amended complaint a month later, yet she had moved within the time the district court’s scheduling order allowed, and the Court saw no reason to fault her.²² The same reasoning disposes of the argument that a plaintiff’s dilatory conduct can defeat relation back. The Rule sets an exclusive list of requirements, the amending party’s diligence is not among them, and the Rule mandates relation back once they are satisfied.²³ The clause likewise asks what the prospective defendant knew or should have known during the period, not what the plaintiff knew when she filed.²⁴

The usual error is to count from the limitations deadline, which was the Schiavone approach and is no longer the law, or to count from the date the plaintiff amended. Neither date appears in the rule’s text.

Notice Without Prejudice

The first showing is that the party to be brought in “received such notice of the action that it will not be prejudiced in defending on the merits.”²⁷ That clause holds two requirements, notice and the absence of prejudice, and each must be satisfied, as the Third Circuit said in Singletary v. Pennsylvania Dept. of Corrections, reading the rule under its earlier numbering.²⁸ Several decisions in this subsection measured notice against the limitations period, as the rule then required or as a state rule still does, so they are useful for what notice and prejudice mean and not for timing.

Notice matters because everything a new party can do to defend depends on when it learned it was in a lawsuit. A party that hears of the suit within weeks can still find witnesses and keep documents while events are fresh, which is why formal service is not required. As Singletary put it, notice does not require actual service of process. It may occur when a party with some reason to expect involvement as a defendant hears of the commencement of litigation through informal means, as when a man the plaintiff later added happened to see a copy of a complaint naming his workplace and an “unknown employee” and knew that the unknown employee was himself.²⁹ The Advisory Committee Notes, quoted in Krupski, likewise say that “the notice need not be formal.”³⁰

Informal does not mean vague. The notice received must be more than notice of the event that gave rise to the cause of action, and it must tell the party that the plaintiff has instituted the action.³¹ A party that knows of an accident knows only that someone may sue someday, and it has no occasion to treat its records as evidence or its employees as witnesses until it learns that a claimant has gone to court.

The decisions that deny relation back for want of notice show the same gap. In Singletary, the district court concluded that Regan did not receive notice of the litigation or of his role in it during the 120-day period, and the Third Circuit agreed. Because the unfair-prejudice issue is closely dependent on the outcome of the notice inquiry, it did not address prejudice.³² Britt v. Arvanitis is another substitution that failed for lack of notice: the company named to replace a placeholder defendant had no notice of the action, formal or informal, before limitations ran.

A plaintiff who cannot show that the new party personally learned of the suit may still show that notice reached it through someone who did. Knowledge of a lawsuit may be imputed to a proposed defendant through a shared attorney, provided the attorney knew or should have known that but for a mistake concerning the proper party’s identity the proposed defendant would be added.³³ Corporate affiliation supplies a second route. In Leonard v. General Motors L.L.C., the court found no prejudice to newly added defendants because all were affiliated with the original defendant, General Motors Company, and therefore had actual or constructive notice of the lawsuit.³⁴ A Kentucky court applying a state rule built on the same wording stated the principle broadly in Halderman v. Sanderson Forklifts Co. Where old and new defendants share a sufficient identity of interest, the notice requirement is satisfied whenever the intended defendant receives notice, “be it actual, informal, imputed, constructive or a combination thereof,” within the limitations period the state rule applies.³⁵ Shared counsel and shared interests are evidence that notice arrived, not extra requirements stacked on top of it.

Prejudice is a separate question: given the notice the new party received, can it still defend on the merits? Here the loss of the limitations defense cannot count, because every amendment that relates back removes that defense, and if the loss were prejudice the clause could never be satisfied. What counts is harm to the defense of the claim itself, such as lost records or unavailable witnesses. A new party that had the suit in hand cannot create prejudice by declining to prepare. In Arthur v. Maersk, Inc., it was undisputed that the claim against the United States arose from the same transactions as the original complaint and that the United States received adequate notice within 120 days and would not be prejudiced.³⁶ In ruling on leave to amend, the Third Circuit added that a “careless or myopic” decision to pursue only “superficial investigatory practices,” despite the likelihood of being named, is not prejudice.³⁷ The logic carries over to the prejudice clause of (C)(i).

When the added defendant is the United States, a short provision replaces much of the proof. If process was delivered or mailed, during the stated period, to the United States attorney or the attorney’s designee, to the Attorney General, or to the officer or agency, the notice requirements of (C)(i) and (ii) are satisfied.³⁸ The provision supplies only those requirements, so the same-transaction requirement of (B) remains.

The second step does the screening in most problems. Notice of an incident, even after a thorough investigation of it, fails that step, while a copy of the complaint seen by chance passes it.

Mistake Concerning Identity

The second showing is that the party to be brought in “knew or should have known that the action would have been brought against it, but for a mistake concerning the proper party’s identity.”⁴⁰ The notice clause asks whether the new party learned that suit had been filed. This clause asks what the new party understood from the suit: whether it should have recognized that it was left out by error and was the intended target. Two questions follow, whose knowledge counts and what counts as a mistake, and the first controls the second.

Krupski answers the first. The plaintiff sued one cruise company and later moved to add Costa Crociere, and the court of appeals denied relation back after examining what she knew. The Supreme Court held that it had chosen the wrong starting point. The question is not whether Krupski knew or should have known the identity of Costa Crociere as the proper defendant, but whether Costa Crociere knew or should have known that it would have been named but for an error.⁴¹ The clause asks what the prospective defendant knew or should have known during the Rule 4(m) period, not what the plaintiff knew when she filed.⁴²

The shift in focus follows from what relation back protects. Repose would be a windfall for a prospective defendant who understood, or should have understood, that it escaped suit only because the plaintiff misunderstood a crucial fact about its identity. A plaintiff’s knowledge that a party exists does not foreclose a mistake of identity about which that party should have been aware, so such knowledge does not support the party’s interest in repose.⁴³

A mistake therefore covers more than a slip of the pen. The simplest case is a misnomer, and an amendment correcting one relates back.⁴⁴ But a plaintiff may also know that party A exists while erroneously believing him to hold the status of party B, or may know generally what A does while misunderstanding the roles A and B played in the events behind the claim. Suing B instead of A in those circumstances is a mistake concerning the proper party’s identity, notwithstanding the plaintiff’s knowledge of both.⁴⁵ The only remaining question is whether A knew or should have known that, absent some mistake, the action would have been brought against him.⁴⁶

The reasonableness of the plaintiff’s error is not itself at issue.⁴⁷ The Rule lists its requirements exclusively, the plaintiff’s diligence is not among them, and once they are met the Rule mandates relation back and leaves nothing to the court’s equitable discretion.⁴⁸ Leonard v. Parry tests the point. After service, defense counsel recognized the confusion over the driver’s identity and called and wrote the plaintiff’s lawyer, yet the plaintiff took no further action within the limitations period.⁴⁹ The First Circuit rejected the premise that carelessness disqualifies a mistake. Virtually every mistake involves some negligence, carelessness, or fault, the rule does not distinguish among types of mistakes concerning identity, and it reaches both easily avoidable mistakes and serendipitous ones.⁵⁰ The examples the Advisory Committee assembled, such as the naming of a nonexistent federal agency or a retired officer, confirm the reading, because the drafters expected such errors to trigger the rule even though reasonable diligence would almost always prevent them.⁵¹ Krupski makes the same observation about the litigants who sued the wrong party in Social Security cases: they may have known or reasonably should have known the proper defendant from their administrative files or the statute, yet the Advisory Committee clearly meant their filings to qualify as mistakes.⁵² Because Leonard fulfilled all of the rule’s requirements, his amendment related back and the dismissal was reversed.⁵³

Related entities make it easier for the new party to see the error. In the General Motors litigation, the court found that similar names, a complex corporate structure, and the 2009 renaming of General Motors Company as General Motors LLC showed how the new defendants knew or should have known that the plaintiff’s failure to sue them was a mistake. It relied on a Second Circuit decision allowing relation back where the name in the caption approximates the correct name, the correct name is not readily identifiable, and the defendant has conducted business under a name easily confused with those of its parent and affiliates.⁵⁴ Other courts have found the same where corporate families blur the lines, as in Goodman v. Praxair, Inc. A mistake about roles can also arise without any confusion of names. The seaman in Arthur sued his statutorily immune employers, and the Third Circuit held that the United States should have known it would have been named but for that mistake.⁵⁵

The fourth step catches the most common exam error, which is to defeat an amendment by pointing to something the plaintiff knew or could have found out, such as a ticket, a corporate filing, or a statute naming the proper defendant. Each of those facts goes to the plaintiff’s knowledge, and it matters only if it also shows what the new party reasonably understood about why it was left out.

Deliberate Choices

Because the rule makes a mistake the condition of relation back, a plaintiff who left a party out on purpose cannot satisfy it. In Krupski, the Supreme Court drew the boundary in these words: “making a deliberate choice to sue one party instead of another while fully understanding the factual and legal differences between the two parties is the antithesis of making a mistake concerning the proper party’s identity.”⁵⁷ The Court then rejected the respondent’s further claim that whenever a plaintiff is aware of two parties and sues the wrong one, the proper defendant could reasonably believe the plaintiff made no mistake.⁵⁸ The boundary therefore has two sides: an informed choice falls outside the rule, and knowledge that the omitted party exists does not by itself show an informed choice.

Each side rests on its own reason. A defendant that reads the original complaint and sees a plaintiff who evidently weighed it and passed has good grounds to believe that limitations ended without any attempt to sue it. If relation back also rescued considered strategy, a plaintiff could sue the defendant who looked like the better target, watch how the case developed, and bring in the second defendant after limitations expired, holding that claim in reserve at no cost. Limiting the rule to errors closes that option.

Knowing that a party exists does not by itself place the plaintiff on the wrong side of the line. A plaintiff may know that a prospective defendant exists and still misunderstand his status or role in the events giving rise to the claim, and suing someone else on that misimpression is a “deliberate but mistaken choice” that does not foreclose relation back.⁵⁹ What matters is whether the plaintiff, knowing both parties, misjudged who stood where.⁶⁰ That is why the Court rejected the court of appeals’ reliance on the plaintiff’s knowledge, since the clause asks about the prospective defendant’s understanding.⁶¹

The prospective defendant’s understanding is built from the original complaint and the plaintiff’s conduct. Krupski read the footnote in Nelson v. Adams USA, Inc. as fully consistent with this view: when the original complaint and the plaintiff’s conduct compel the conclusion that the failure to name the prospective defendant was the result of a fully informed decision, as opposed to a mistake concerning the proper defendant’s identity, the requirements of the clause are not met.⁶² The standard turns on whether the record compels that conclusion, which sets a demanding threshold. The Third Circuit has explained its own decision in Nelson v. County of Allegheny on the same footing: the plaintiffs there were aware of their claims against the defendants when the case was commenced but decided not to sue them. The court noted that the result seems to import the “undue delay” factor of Rule 15(a) into Rule 15(c), and it justified the holding on the plaintiffs’ informed decision.⁶³

The plaintiff’s knowledge and conduct are not irrelevant everywhere. What the plaintiff knew or should have known and what she did or should have done bear on whether justice requires leave to amend under Rule 15(a), a discretionary provision, but they do not decide whether an amendment relates back under Rule 15(c).⁶⁴ The seaman in Arthur shows how the record can point the other way. There was no basis for characterizing his decision to sue his statutorily immune employers as litigation strategy, and nothing suggested that the government viewed it that way.⁶⁵

John Doe Defendants

A recurring fact pattern strains the mistake clause. A plaintiff sues “unknown police officers” or a defendant designated John Doe before limitations ends, learns the real names through discovery after it has run, and moves to substitute them. The officers may have known of the suit within the Rule 4(m) period and known that they were its targets, so notice and knowledge could be satisfied. The first question remains whether the plaintiff’s failure to name them was a mistake at all, and the circuits are divided.

The question arises in civil rights litigation because of who holds the identifying information. A person assaulted by police officers or prison guards is often unaware of their identities, the defendants hold that information, and many plaintiffs cannot obtain it until they have undergone extensive discovery after the suit is filed.⁶⁷ A plaintiff who files near the end of the limitations period has no time to learn the names before it closes, so relation back is the only device that could save the claim against the individuals.

The weight of authority holds that the rule was not written to supply that rescue. The Third Circuit counted the First, Second, Fourth, Fifth, Sixth, Seventh, and Eleventh Circuits as holding that substituting real names for “John Does” or “Unknown Persons” does not meet the “but for a mistake” requirement, because not knowing a defendant’s identity is not a mistake concerning that identity.⁶⁸ The group includes Wilson v. United States in the First Circuit and, in the Seventh Circuit, Wood v. Worachek and Worthington. A mistake is a wrong belief, and a plaintiff who sues an “unknown” officer holds no wrong belief about who the officer is. The adversary system adds a second reason. As the District of Columbia Circuit has written, the plaintiff is responsible for determining who is liable for her injury, and for doing so before the limitations period runs, and if she later discovers another possible defendant she may not, merely by invoking Rule 15(c), avoid the consequences of her earlier oversight.⁶⁹

The majority rule has a boundary that matters on exam facts. A plaintiff who knows that individual defendants must be named but lacks their names stands on one side. A plaintiff who holds a wrong belief about whom to sue stands on the other. In the General Motors litigation, the court distinguished a Second Circuit decision that refused relation back for officers the plaintiff could not name. Nothing suggested that the plaintiff there knew additional defendants should have been sued, and the circumstances compelled the opposite conclusion: he named no John Doe defendants and learned of the correct entity only from the defendants’ initial disclosures, three months after filing and about a month before limitations was to expire.⁷⁰

The Third Circuit’s precedent runs the other way. In Singletary, the court acknowledged that it was bound by an earlier decision holding that a plaintiff’s lack of knowledge of a defendant’s identity can be a mistake under the rule, and that every other circuit to consider the issue had gone the other way, mostly on the linguistic ground that lack of knowledge is not a “mistake.”⁷¹ The court gave reasons for thinking the majority wrong. Plaintiffs who do not know the names are effectively given a shorter limitations period than those who do, since they must sue early, begin discovery at once, and hope to learn the names in time, and nothing justifies disadvantaging them because, for example, they could not see a name tag.⁷² The court also proposed rewording the clause to cover “a mistake or lack of information concerning the identity of the proper party,” a change that would align the rule with the liberal pleading policy of the Federal Rules.⁷³ The district judge in Worthington reached a similar view of the text, reasoning that the word “mistake” does not create a new prerequisite but refers back to the phrase “change the party or the naming of the party.”⁷⁴ A dissent in Arthur v. Maersk, Inc. objected that the Third Circuit’s decision was at odds with the other circuits.⁷⁵ Some courts have revisited the majority approach since Krupski, as in White v. City of Chicago. Krupski did not decide the Doe question, because its plaintiff knew the omitted party existed and misjudged its role, whereas a Doe plaintiff does not know who the party is.

Even under the permissive view, the other clauses still protect defendants. They generally prevent springing a claim on an unsuspecting defendant, so the mistake requirement as the other circuits read it is dispositive only when the new party had timely notice and knew the suit was aimed at it.⁷⁶ Singletary shows that protection at work. The original complaint named “Unknown Corrections Officers,” and the court doubted that Regan, a psychologist, would have had any way of knowing that the plaintiff meant him.⁷⁷

State law may offer a separate route for placeholder defendants. A federal court applying California’s Doe practice refused to deny plaintiffs the three-year extension of limitations that California’s Doe rules provide merely because they had not strictly complied with the requirement that the new defendant be named and served as a person sued under a fictitious name. The plaintiffs had filed an amended complaint naming the new defendant, dropped the Doe defendants as named parties, and stated that the new parties were added in lieu of the Doe designation, and federal procedure permitted them to do no more.⁷⁸

The usual error is to treat Krupski as having decided that placeholder substitutions relate back, or to assume that a Doe plaintiff wins whenever the new party had notice. Under the majority view, notice is necessary and cannot supply a missing mistake. Under the permissive view, it must still be paired with knowledge that the suit was aimed at the new party.

Added Parties and Plaintiffs

Rule 15(c)(1)(C) permits relation back for an amendment that changes “the party or the naming of the party against whom a claim is asserted,” and the preceding subsections read that language mainly as a device for replacing a wrong defendant with the right one.⁸⁰ Two extensions remain: does the rule also reach an amendment that adds a defendant while the original defendant stays in the case, and does anything like it govern a change on the plaintiff’s side, which the text never mentions? A footnote in Krupski supplies part of the first answer. The rule speaks generally of an amendment to a pleading that changes the party against whom a claim is asserted, so it is not limited to a plaintiff’s amended complaint bringing in a new defendant, and the Court used that scenario as shorthand only because it is the typical case.⁸¹ The footnote does not decide the added-defendant question and says nothing about plaintiffs, so both extensions depend on how lower courts have reasoned from the rule’s purpose.

The obstacle to adding defendants is the mistake clause. Several courts in the Second Circuit have concluded that (C) encompasses only “wrong party” cases and not “additional party” cases, because an additional-party case generally involves no mistake concerning the proper party’s identity.⁸² That reading follows from the text, since (C)(ii) makes a mistake the condition of relation back, and a plaintiff who sued a proper defendant and later decides to sue a second one has corrected nothing.⁸³ The reading breaks down when the plaintiff’s choice of the first defendant was itself the product of an error about who answers for the injury.

That was the situation in Leonard v. General Motors L.L.C. The cause of action accrued on January 5, 2017, the date of the accident, and the complaint against General Motors Company, filed on August 21, 2019, was timely, but the motion to add affiliated entities, filed on February 3, 2020, was not.⁸⁴ The court treated the plaintiff as one who mistakenly believed that suing the original defendant would suffice and found that the new defendants had no reason to think otherwise, a conclusion reinforced by their similar names, their complex corporate structure, and the 2009 renaming of General Motors Company as General Motors LLC.⁸⁵ The court called the narrower reading too restrictive, because it fails to apply the lessons of Krupski. Allowing the amended complaint to relate back furthers the goal of deciding claims on their merits without prejudicing the defendants.⁸⁶ For an added defendant, as for a substituted one, the question remains what the new party knew or should have known during the Rule 4(m) period.⁸⁷

The fact that separates the two lines of authority is the source of the plaintiff’s original choice. A plaintiff who sued one entity because of an error about which company played which role has made the mistake (C)(ii) requires, and adding rather than swapping does not change that error. A plaintiff who understood the second entity’s role and held it in reserve has made the deliberate choice discussed in the previous subsection, and relation back fails whether the amendment adds or substitutes. An older decision, Koal Industries Corp. v. Asland, S.A., allowed relation back for officers of the original corporate defendant, who were aware of possible litigation because similar claims had been asserted against the company’s officers and who should have known that the plaintiffs were likely to file these claims once discovery supported an amended complaint.⁸⁸ It illustrates the close-relationship and no-prejudice reasoning that the notice clause makes explicit.

The plaintiff side has no textual footing at all, because (C) speaks of the party against whom a claim is asserted, which describes defendants. Courts that allow a change of plaintiff after limitations has run therefore borrow the rule’s policy by analogy, so the authorities below are offered for their reasoning and do not establish a settled federal rule on added plaintiffs. In Beal v. City of Seattle, the Washington Supreme Court observed that the federal decisions allowing relation back for changes in a plaintiff’s capacity discussed no mistake in identifying the proper party, and that the relevant inquiry in them, and in its own court of appeals’ decisions, was whether the defendant was prejudiced.⁸⁹

Where the change adds a different person as plaintiff, courts ask a second question, whether the new plaintiff’s claim rests on the same underlying conduct. re Simon II Litigation illustrates the point through a Second Circuit decision, Benfield v. Mocatta Metals Corp. There an options purchaser who sued over a futures merchant’s fraud amended to add a RICO count and a similarly aggrieved purchaser as a second plaintiff, and the court held that the defendant could not assert the statute of limitations as a defense to the new plaintiff’s RICO charge.⁹⁰ A court deciding whether to accept a new plaintiff therefore asks whether the defendant could have been surprised by the addition.

The usual error runs in two directions. One is to conclude that because (C) mentions only the party against whom a claim is asserted, no change of plaintiff can ever relate back. The other is to treat any added plaintiff as covered because the original lawyer is the same. Courts that allow the change ask whether the defendant had notice and will not be unfairly prejudiced and whether the added plaintiff’s claim rests on the same operative facts, and the answer to both questions turns on what the defendant knew about the dispute when the original suit was filed.