United States Court of Appeals 

For the First Circuit 

No. 14-2145 

UNITED STATES OF AMERICA ex rel. JEFFREY D'AGOSTINO, 

Plaintiff, Appellant, 

STATE OF CALIFORNIA, ET AL., 

Plaintiffs, 

v. 

EV3, INC., JOHN HARDIN, MICROTHERAPEUTICS, INC., 

and BRETT WALL, 

Defendants, Appellees. 

APPEAL FROM THE UNITED STATES DISTRICT COURT 

FOR THE DISTRICT OF MASSACHUSETTS 

[Hon. Richard G. Stearns, U.S. District Judge] 

Before 

Howard, Chief Judge, 

Selya and Lipez, Circuit Judges. 

 Daniel R. Miller, with whom Susan Schneider Thomas, Berger & 

Montague, P.C., Lynn Weissberg, Jonathan Shapiro, and Stern, 

Shapiro, Weissberg & Garin LLP were on brief, for appellant. 

 Joshua S. Levy, with whom Mitchell Stromberg, Bryan 

Pennington, and Ropes & Gray LLP were on brief, for appellees ev3, 

Inc. and Microtherapeutics, Inc. 
 Stephen G. Huggard, with whom Elizabeth H. Kelly and Locke 

Lord LLP were on brief, for appellee John Hardin. 

 Martin F. Murphy, Amanda S. Hainsworth, and Foley Hoag LLP on 

brief for appellee Brett Wall. 

September 30, 2015 
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SELYA, Circuit Judge. Plaintiff-appellant Jeffrey 

D'Agostino (the relator) challenges both the dismissal of his qui 

tam action and the antecedent denial of leave to further amend his 

complaint. For obvious reasons, we consider the second challenge 

first. That challenge rests in part on a novel interpretation of 

the 2009 amendments to Rule 15 of the Federal Rules of Civil 

Procedure. While we reject that novel interpretation, we 

nonetheless conclude that the district court appraised the 

relator's request for leave to amend under the wrong legal 

standard. Consequently, we vacate the judgment below and remand 

for further proceedings. 

I. BACKGROUND

In October of 2010, the relator filed a qui tam action 

on behalf of the United States, twenty-five states, and the 

District of Columbia. His complaint named his former employer — 

ev3, Inc. — as the sole defendant and asserted a golconda of claims 

under the False Claims Act (FCA), 31 U.S.C. §§ 3729-3733, and 

analogous state statutes. The gravamen of these claims was the 

charge that ev3 had engaged in improper conduct in connection with 

the manufacturing and marketing of two medical devices (Onyx and 

Axium) and had knowingly caused health-care providers to submit 

false claims to various government entities. 
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The complaint was filed under seal and service was 

initially suspended. See id. § 3730(b)(2). In February of 2011, 

the relator exercised his unilateral right to file an amended 

complaint as a matter of course. See Fed. R. Civ. P. 15(a)(1). 

The relator thereafter filed second and third amended complaints 

(in August 2012 and April 2013, respectively), having obtained 

leave of court in each instance. These amendments added five 

defendants and reconfigured the relator's legal theories. 

The action remained under seal while the United States 

looked into the relator's charges. In October of 2013, the United 

States decided not to intervene. See 31 U.S.C. § 3730(b)(4)(B). 

The court thereafter unsealed the docket and authorized service of 

process. The following May, the parties jointly moved to have the 

district court set a deadline of June 30 for the filing of motions 

to dismiss and July 25 for the filing of the relator's opposition. 

The court obliged and, in the process, made clear that it would 

grant no further extensions of these deadlines. 

The defendants timely filed their motions to dismiss. 

They argued that the court lacked jurisdiction by reason of the 

FCA's public disclosure bar, see id. § 3730(e)(4), and that the 

third amended complaint failed either to state a cognizable claim 

or to plead fraud with sufficient particularity. About a week 

later, the court entered a scheduling order pursuant to Federal 
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Rule of Civil Procedure 16(b), which set forth a series of temporal 

benchmarks that would take effect after it decided the motions to 

dismiss. The order did not set a deadline for amendments to the 

pleadings. 

Four days before his opposition to the motions to dismiss 

was due, the relator filed a fourth amended complaint. This 

edition of the complaint dropped claims against two defendants, 

abandoned certain legal theories, and added factual allegations 

responsive to the motions to dismiss. Instead of requesting leave 

to amend, the relator filed an accompanying motion asserting that 

he had an absolute right to amend his complaint under Federal Rule 

of Civil Procedure 15(a)(1) and asking the district court to set 

a new briefing schedule. 

The defendants moved to strike the fourth amended 

complaint, arguing that the relator had already exhausted his one 

amendment as of course. They added that the court should not treat 

his motion as a request for leave to amend. The court agreed that 

the relator had used up his one-time right to amend as a matter of 

course. But the court construed the relator's filings liberally 

as a request for leave to amend, concluded that Rule 16(b)'s "good 

cause" standard governed the request, and held that the relator 

had not established good cause for amending his complaint once 

again. Accordingly, it granted the motion to strike. 
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The relator subsequently filed his opposition to the 

motions to dismiss,1 which included a short section conditionally 

requesting leave to amend the complaint further should the court 

determine that any claims were subject to dismissal. Counsel 

reiterated that request several times at the ensuing hearing on 

the motions to dismiss. The district court reserved decision and 

subsequently dismissed the case with prejudice. In its written 

rescript, the court concluded that the FCA's public disclosure bar 

deprived it of jurisdiction over certain allegations. See United 

States ex rel. D'Agostino v. ev3, Inc., No. 10-11822, 2014 WL 

4926369, at *5-6 (D. Mass. Sept. 30, 2014). As to the remaining 

allegations, the court ruled that the third amended complaint 

failed to identify any false claims with the specificity demanded 

by Federal Rule of Civil Procedure 9(b) and also failed to state 

a cognizable claim. See id. at *6-9. The court's rescript did 

not address the relator's conditional request for leave to amend. 

II. ANALYSIS

On appeal, the relator advances two basic claims of 

error. First, he contends that the district court improperly 

thwarted his efforts to amend his complaint. Second, he challenges 

 1

  By a separate filing, the relator voluntarily dismissed his 

claims against the two defendants whom he had dropped in the 

proposed fourth amended complaint. 
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the court's dismissal of his complaint and the subsidiary legal 

determinations undergirding that dismissal. We start — and end — 

with the first claim of error. 

We review the grant or denial of leave to amend for abuse 

of discretion. See Nikitine v. Wilmington Trust Co., 715 F.3d 

388, 389 (1st Cir. 2013). In conducting this tamisage, we defer 

in substantial measure to the trial court's hands-on judgment and, 

thus, we will affirm "so long as the record evinces an arguably 

adequate basis for the court's decision." Hatch v. Dep't for 

Children, Youth & Their Families, 274 F.3d 12, 19 (1st Cir. 2001). 

This deference, though, is not boundless. A trial court may abuse 

its discretion when, among other things, it adopts and applies the 

wrong legal rule. See Waste Mgmt. Holdings, Inc. v. Mowbray, 208 

F.3d 288, 295 (1st Cir. 2000). 

To put the relator's assignment of error in perspective, 

we rehearse the applicable procedural framework. Requests to amend 

a complaint are typically evaluated under Rule 15, which provides 

that 

[a] party may amend its pleading once as a 

matter of course within: 

 (A) 21 days after serving it, or 

 (B) if the pleading is one to which a 

responsive pleading is required, 21 days after 

service of a responsive pleading or 21 days 

after service of a motion under Rule 12(b), 

(e), or (f), whichever is earlier. 
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Fed. R. Civ. P. 15(a)(1). Once a party has exhausted its one-time 

right to amend as a matter of course, it may make further 

amendments only with the opposing party's consent or with leave of 

court. See id. 15(a)(2). The rule cautions, however, that the 

court should "freely give" leave to amend where the interests of 

justice so require. Id. 

At a certain point, this amendment-friendly regime may 

cease to govern. Rule 16 directs a district court to issue a 

scheduling order charting the anticipated course of the 

litigation. See id. 16(b)(1). One customary element of such an 

order is a deadline for amending the pleadings. See id. 

16(b)(3)(A). Such a deadline, like other deadlines contained in 

a scheduling order, may be modified only upon a showing of "good 

cause." Id. 16(b)(4). Thus, when a litigant seeks leave to amend 

after the expiration of a deadline set in a scheduling order, Rule 

16(b)'s more stringent good cause standard supplants Rule 15(a)'s 

leave freely given standard. See, e.g., Cruz v. Bristol-Myers 

Squibb Co., P.R., Inc., 699 F.3d 563, 569 (1st Cir. 2012); TransSpec Truck Serv., Inc. v. Caterpillar Inc., 524 F.3d 315, 327 (1st 

Cir. 2008). 

Against this backdrop, we turn to the relator's 

assignment of error. To begin, he hypothesizes that Rule 15(a)(1) 

granted him an absolute right to file the fourth amended complaint 
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without first obtaining leave of court. This hypothesis is nothing 

more than wishful thinking. 

Rule 15(a)(1) explicitly states that a party is entitled 

to amend "once as a matter of course." Fed. R. Civ. P. 15(a)(1) 

(emphasis supplied); see United States ex rel. Poteet v. Bahler 

Med., Inc., 619 F.3d 104, 116 (1st Cir. 2010). The relator took 

advantage of this one-time opportunity in February of 2011 when he 

filed his first amended complaint. Absent the defendants' consent 

— never obtained here — the relator was therefore obligated to 

secure leave of court before any further amendments to his 

complaint could be effected. 

The relator demurs. He reasons that, pursuant to the 

2009 revisions to Rule 15, amendment as a matter of course may be 

made "within . . . 21 days after service of" a defendant's answer 

or responsive motion, Fed. R. Civ. P. 15(a)(1)(B), so such 

amendments may be made whenever such an action has occurred. Under 

this construction, his right to amend as a matter of course renewed 

each time the defendants filed a responsive pleading (either an 

answer or a responsive motion) to a particular version of the 

complaint.2

 

 2 At oral argument, the relator's counsel disclaimed any 

reliance on a theory that service of the complaint is required to 
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This tortured interpretation of Rule 15 not only defies 

common sense but also runs contrary to the historic structure of 

Rule 15 and to the stated purpose of the 2009 amendments to the 

Rule. Prior to those amendments, Rule 15(a)(1) stated: 

A party may amend its pleading once as a matter 

of course: 

(A) before being served with a responsive 

pleading; or 

(B) within 20 days after serving the pleading 

if a responsive pleading is not allowed and 

the action is not yet on the trial calendar. 

Fed. R. Civ. P. 15(a)(1) (2009). This language made plain that a 

plaintiff is allowed to amend as a matter of course at any time 

between filing his complaint and receiving the defendant's answer. 

But the 2009 revisions did not purpose to alter the time at which 

a plaintiff can first amend as a matter of course. The absence of 

such a change is understandable: those revisions were intended 

primarily to remedy inefficiencies created by granting plaintiffs 

the unconditional right to amend as a matter of course at any time 

before an answer was filed (regardless of how much litigation and 

discovery activity had occurred in the interim). See 6 Charles 

Alan Wright et al., Federal Practice and Procedure, § 1483 (3d ed. 

 

trigger the right to amend as of course under Rule 15(a)(1)(A). 

Accordingly, we take no view on that theory. 
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2010). To that end, the drafters made "three changes in the time 

allowed to make one amendment as a matter of course." Fed. R. 

Civ. P. 15 advisory committee's note to 2009 amendment. 

Two of these changes are arguably relevant here.3 The 

Rule was revised so that "the right to amend once as a matter of 

course [now] terminates 21 days after service of a motion under 

Rule 12(b)" and "is no longer terminated by service of a responsive 

pleading." Id. The advisory committee's focus on the time at 

which the right to amend terminates and its concomitant silence 

concerning changes to when such an amendment may first be made 

makes abundantly clear that, in this context, the word "within" 

merely specifies the point at which the right expires. 

Nothing else in either the text of Rule 15 or in the 

advisory committee's notes evinces an intent to confine amendments 

as a matter of course under Rule 15(a)(1)(B) to a narrow window 

following service of an answer or responsive motion. Nor do these 

materials evince any intent to rescind the historic limitation of 

amendment as a matter of course to one such amendment per plaintiff 

per case. The Rule's traditional restriction of amendments as a 

 

 3 The third change addressed the amendment of pleadings to 

which no responsive pleading is required. That provision is not 

implicated here. 
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matter of course to one per plaintiff per case was not modified. 

Had the drafters intended so dramatic a change in long-settled 

procedure, they surely would have chosen language indicating as 

much and explained this change in the commentary. Here, however, 

the advisory committee's notes imply the contrary; they discuss 

changes only to the time at which the right to amend as a matter 

of course terminates. 

To say more on this point would be supererogatory. We 

hold, without serious question, that a plaintiff may amend a 

complaint only once as a matter of course under Rule 15(a)(1). It 

follows that the district court did not err in concluding that the 

relator exhausted his one-time right to amend as a matter of course 

when he filed his first amended complaint in February of 2011. 

This brings us to the relator's claim that even if he 

did not have an unfettered right to amend his complaint in July of 

2014, the district court abused its discretion by appraising the 

proposed amendment under the wrong legal standard. While the 

district court might have struck the fourth amended complaint on 

the ground that the relator filed it without requesting leave to 

amend, that is not what happened. Instead, the court construed 

the relator's filing as an implicit request for leave to amend. 

We defer to this reasonable construction of the relator's filing. 

Cf. Invest Almaz v. Temple-Inland Forest Prods. Corp., 243 F.3d 
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57, 71 (1st Cir. 2001) (construing new argument raised in 

opposition to motion for judgment as a matter of law as a request 

for leave to amend). 

Having decided that the question of leave to amend was 

properly before it, the court proceeded to answer that question by 

applying Rule 16(b)'s good cause standard. In the circumstances 

of this case, that was error. Cf. Somascan, Inc. v. Philips Med. 

Sys. Nederland, B.V., 714 F.3d 62, 64 (1st Cir. 2013) (per curiam) 

(holding that the good cause standard, rather than the leave freely 

given standard, applies when a scheduling order sets a deadline 

for amending the pleadings). 

As we previously explained, requests for leave to amend 

are normally evaluated under Rule 15(a)'s leave freely given 

standard. When made in derogation of a scheduling order, however, 

Rule 16(b)'s more stringent good cause standard takes precedence. 

See id. But in this case the district court's scheduling order 

did not specify any deadline for amending the pleadings and, thus, 

the gears of Rule 16(b) were not engaged. 

Notwithstanding this omission in the scheduling order, 

the court applied Rule 16(b). It reasoned that use of the good 

cause standard was an appropriate way to sanction the relator for 

requesting leave to amend within a matter of days before his 
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opposition to the dismissal motions was due. This reasoning is 

unpersuasive. 

When a litigant seeks leave to amend in defiance of a 

deadline delineated in a scheduling order, the rationale for 

applying an elevated good cause standard is both obvious and 

pragmatic. Were a district court powerless to enforce such 

deadlines, scheduling orders would be little more than 

aspirational statements, to be disregarded by the parties whenever 

compliance proves inconvenient. See O'Connell v. Hyatt Hotels of 

P.R., 357 F.3d 152, 155 (1st Cir. 2004). Properly deployed, the 

elevated good cause standard puts teeth into Rule 16(b) scheduling 

orders and "preserves the integrity and effectiveness of [such] 

scheduling orders." Id. In other words, the specter of Rule 

16(b)'s less amendment-friendly standard acts as one of the sticks 

through which compliance with a scheduling order is enforced. 

Deployment of the good cause standard was not warranted 

here. Since the scheduling order in this case did not even mention 

amendments to the pleadings, let alone impose any deadlines for 

the filing of amended pleadings, moving to amend did not show any 

disrespect for court orders. Moreover, the relator had neither 

notice that an elevated standard would be applied to his motion 

nor any reason to expect that it would. Basic notions of due 

process counsel that litigants are entitled to rely on established 
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procedural rules — and those rules cannot be altered at a court's 

whim. Cf. Landgraf v. USI Film Prods., 511 U.S. 244, 265 (1994) 

("Elementary considerations of fairness dictate that individuals 

should have an opportunity to know what the law is and to conform 

their conduct accordingly; settled expectations should not be 

lightly disrupted.").

The fact that the relator sought to amend only a few 

days before his opposition to the dismissal motions was due does 

not justify a different result. At any rate, Rule 15(a)'s leave 

freely given standard typically applies even where a party requests 

leave to amend after a motion to dismiss has been fully briefed. 

See, e.g., Palmer v. Champion Mortg., 465 F.3d 24, 30 (1st Cir. 

2006). If the court concluded that the relator was attempting to 

torpedo its briefing schedule, that conclusion could be a proper 

factor in its Rule 15(a)(2) calculus, see Quaker State Oil Ref. 

Corp. v. Garrity Oil Co., 884 F.2d 1510, 1517-18 (1st Cir. 1989), 

but it could not be a permissible ground for employing a more 

stringent standard. 

The defendants contend that the court's failure to 

specify a deadline for amending the pleadings is irrelevant because 

the court must have thought — based on the travel of the case — 

that there would be no further amendments to the complaint when it 

issued its scheduling order. But nothing of this sort is apparent 
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from the record, and the relator could not be expected to divine 

from the district court's silence that future amendments were 

either off limits or would be subjected to a more stringent 

standard of review. See Weisburgh v. Fidelity Magellan Fund (In 

re Fidelity/Micron Sec. Litig.), 167 F.3d 735, 737 n.1 (1st Cir. 

1999). We hold, therefore, that the district court erred in 

applying Rule 16(b)'s good cause standard to the relator's proposed 

fourth amended complaint. 

The matter of remedy remains. Ordinarily, a district 

court's application of an erroneous legal standard is a per se 

abuse of discretion, which necessitates remand. See In re Grand 

Jury Subpoena, 138 F.3d 442, 444, 445-46 (1st Cir. 1998). There 

is, however, a narrow exception for instances in which application 

of the correct legal standard can lead to only one result. See 

id. at 446. Where uncertainty lurks, remand is the appropriate 

course. See United States ex rel. Rost v. Pfizer, Inc., 507 F.3d 

720, 733-34 (1st Cir. 2007). 

We cannot say with certainty that the district court 

would not have allowed the fourth amended complaint if it had 

applied the appropriate legal standard. Rules 15(a) and 16(b) 

engender different inquiries. See O'Connell, 357 F.3d at 155. 

Here, the district court made no findings sufficient to permit us 
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to predict confidently how it would have ruled under the Rule 15(a) 

standard.4

Let us be perfectly clear. We do not suggest that the 

district court will be compelled to grant the motion to amend on 

remand. After all, there are myriad reasons that might justify 

the denial of a motion for leave to amend, including undue delay, 

repeated failure to cure deficiencies, or futility. See Foman v. 

Davis, 371 U.S. 178, 182 (1962). "The number and nature of prior 

amendments to a complaint" are also relevant considerations. ACA 

Fin. Guar. Corp. v. Advest, Inc., 512 F.3d 46, 56 (1st Cir. 2008). 

The rub, however, is that the district court did not address these 

factors in any meaningful way, and none of them appears to mandate 

the denial of leave to amend. In the last analysis, the matter is 

one committed to the sound discretion of the district court, and 

the relator is entitled to have the district court exercise that 

discretion under the proper legal standard. 

 4 To be sure, the district court's order denying leave to 

amend alludes conclusorily to prejudice to the defendants. 

However, that order provides no detail; and the possibility that 

the defendants will be seriously prejudiced by allowing amendment 

at this relatively early stage of the litigation seems sufficiently 

remote to warrant remanding the matter to the district court for 

further consideration. 
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III. CONCLUSION

We need go no further.5 For the reasons elucidated 

above, the judgment below is vacated and the case is remanded for 

further proceedings consistent with this opinion. All parties 

shall bear their own costs. 

Vacated and remanded.

 5 Because we are uncertain of what result the district court 

will reach when it applies the correct legal standard to the 

relator's request to file the fourth amended complaint, we take no 

view of the substantive issues briefed by the parties. There is 

simply too great a risk that any decision concerning those issues 

will turn out to be purely advisory. See United States v. Tyerman, 

641 F.3d 936, 936 n.2 (8th Cir. 2011) (declining to address 

additional issues raised on appeal where it was "unknown if and 

how th[e] case w[ould] proceed on remand").