If you have two workers’ compensation claims from two separate accidents, and both accidents hurt the same part of you, one question takes over once the case reaches permanency: how will the doctor divide it up? And what happens if the report does not divide it at all?
The honest answer has three parts. Your doctor is probably not required to address it. Between two established claims it usually does not change what you receive. And in some situations you are the one who should be asking for it — which is the part nobody tells claimants.
What apportionment is
Apportionment divides responsibility for one permanent condition among two or more causes. The Workers’ Compensation Board’s glossary describes it as a proportionate division of all or part of the benefit costs between two or more injury claims for the same claimant, based on the relative contribution each injury made to the permanent disability.
Note what that definition covers and what it does not. It describes apportionment between claims. Apportionment can also run to something that was never a claim at all — a prior condition that was not work-related. Those two situations work very differently, and the difference is where the money is.
Your doctor is generally not required to address it
No statute, regulation or Board guideline generally requires a treating physician’s permanency report to apportion between two accidents in a traumatic injury case. The regulation governing permanency reports requires an opinion on whether there is permanent impairment. It says nothing about apportionment.
The Workers’ Compensation Law does address related ground. Section 44 provides for apportionment among successive employers in occupational disease cases, and Section 15(7) limits compensation where a previous disability exists. Neither directs a physician to apportion a traumatic injury between two accidents.
Apportionment in an accident case is a question of fact raised by a party and decided by the Board. As the Appellate Division put it in Matter of Birro v. Wolkow-Braker Roofing Corp. (2024), apportionment presents a factual issue for the Board to resolve, and its resolution stands if supported by substantial evidence.
What Form C-4.3 actually asks
Form C-4.3 — the Doctor’s Report of MMI/Permanent Impairment — never uses the word apportionment anywhere on it.
Attachment A, used for schedule loss of use, comes closest. It asks about previously received schedule loss of use awards to the same body part, if known, and where one exists asks the physician to state with specificity what percentage is attributable solely to the injury being evaluated. The trigger is a prior award already made — not any prior injury.
Attachment B, used for non-schedule injuries, contains no apportionment question. Its only related item asks whether the patient has had an injury since the date of injury that affects residual functional capacity, and asks for an explanation rather than a percentage.
Brain injuries are never schedule cases
Section 15(3) lists the body parts carrying a schedule award: arm, leg, hand, foot, eye, thumb, fingers, toes and loss of hearing. The brain is not among them. The only item addressing the head itself, as distinct from the eyes or hearing, is Section 15(3)(t), which covers serious facial or head disfigurement — appearance, not brain function.
Brain impairment is evaluated as a non-schedule permanent partial disability under Section 15(3)(w), using Chapter 15 of the Board’s 2012 Guidelines. The 2018 Guidelines cover schedule loss of use only; the 2012 chapters still govern non-schedule impairments, including the brain.
So if your permanency is a brain classification, Attachment A’s prior-award question does not apply to it. That does not mean apportionment is irrelevant to your case — read on.
Between two established claims, apportionment usually splits the carriers’ bill
Where two claims are both established and both contribute to one permanent condition, the Board assigns percentages and the carriers divide the cost — 50/50 in Matter of Ferrari v. Frito Lay and Matter of Campbell v. Interstate Materials Corp., and 80% to the later claim with 20% to a much older one in Matter of Young v. LP Transp.
On the record in the first Birro appeal, in 2023, the Appellate Division dismissed the claimant’s challenge to an apportionment ruling because he was not aggrieved by it: that decision, the court said, in no way implicated his entitlement to awards and addressed only which entity was responsible for paying them.
That is the usual shape of it. It is not a rule that apportionment never touches a claimant — the same court heard the same claimant’s apportionment appeal on the merits the following year.
Old injuries that were never a claim
This is the kind of apportionment that can actually come out of your award, so it is worth understanding even if it does not apply to you.
The general rule protects you. When a prior condition did not come from a compensable injury, apportionment generally does not apply if you were able to effectively perform your job despite that condition when the work accident happened. The question is not whether the old condition shows up in your records, or even whether it bothered you now and then. It is whether it was a disability in the compensation sense: whether it was actually limiting your ability to work.
Schedule loss of use cases have a narrow exception. Apportionment may apply if the medical evidence shows that the old injury, had it been compensable, would itself have resulted in a schedule loss of use. In other words, the carrier has to show measurable loss of use, under the Board’s guidelines, before the work accident.
Courts hold carriers to that proof. In Matter of Hughes v. Mid Hudson Psychiatric Center (2021), the carrier’s examiner attributed most of a 45% schedule loss of use of the leg to a 1976 knee injury that had led to six surgeries but had never been a claim, and the Board apportioned part of the award to it. The Appellate Division reversed. There were no operative or pathology reports from the old surgeries, and nothing showing the knee had measurable loss of use before the work injury. The court upheld Board decisions refusing apportionment for the same kind of reason in Matter of Fisher v. Erie County Sheriff’s Department (2021) and in a 2022 case involving an ankle injury from about 40 years earlier.
So two questions matter about any old injury in your file. Was it stopping you from working? And is there medical evidence from before the work accident showing measurable loss of use? When the answer to both is no, an apportionment argument built on an old injury usually fails.
Sometimes you are the one who wants apportionment
This is the part that surprises people, and it is why blanket advice about apportionment is dangerous.
The durational caps on non-schedule awards under Section 15(3)(w) apply only to accidents on or after March 13, 2007. A claim with an earlier accident date is not capped. If you have one claim on each side of that date, shifting weight onto the older claim can convert a capped award into one that is not.
That is precisely what the claimant in Birro was fighting for in 2024. The trial judge had apportioned 80% to his uncapped 2006 claim and 20% to his 2015 claim. The Board rescinded that and placed everything on the 2015 claim. The claimant appealed — arguing the Board was wrong to reject apportionment. He was the one who wanted it.
Date of accident matters in a second way. The maximum weekly benefit rate is set by the date of the accident and does not rise later when the maximum changes. Two accidents a few months apart can fall on either side of a July 1 rate change, which means the two claims may not pay at the same rate.
Two claims does not make apportionment automatic
It is tempting to assume two established claims to the same body part must produce a split. They do not.
In Birro, the 2015 carrier’s orthopedic surgeon offered the only apportionment opinion in the record, and the Board rejected it outright. The claimant had kept working after the 2006 injury, there was little documented treatment in the years between, and the surgery followed the 2015 accident. The opinion, the Board found, was not borne out by the record.
What actually decides it: your work history and your treatment records
An adverse apportionment opinion usually arrives through the carrier’s independent medical examination, so that report is worth reading closely when it lands.
The Board is not obliged to accept an apportionment opinion simply because it is the only one offered. It may reject an opinion that is speculative or lacks evidentiary support in the record even where nothing contradicts it.
A 2024 decision shows how that plays out, and from an unusual direction. The claimant himself wanted apportionment, and offered the only medical opinion on it — an orthopedic surgeon splitting 80% to his 2006 accident and 20% to a 2015 fall. Nothing contradicted it. The Board rejected it anyway and the Appellate Division affirmed: he had continued working after 2006, the most recent medical evidence on that claim was a report from 2010, and he did not have surgery on his back or knee until after the 2015 incident. An uncontradicted opinion still has to rest on something. (Matter of Birro v Wolkow-Braker Roofing Corp., 3d Dept, Apr. 18, 2024, Docket No. 535730.)
What gives such an opinion support, or takes it away, is ordinary documentary history. Were you working without restriction between the two accidents? Were you treating during that period, and how often? What do the objective findings show before and after each accident?
There is a limit in the other direction as well. In Hughes, the Board found both experts’ percentages speculative and then built its own figure from the Guidelines. The Appellate Division would not allow it: the Board may reject medical evidence as insufficient, but it may not fashion its own medical opinion.
Know which answer helps you before the question comes up
Whether apportionment helps or hurts you depends on facts that are not obvious from the exam room — the accident dates, whether either claim predates March 2007, the benefit rate on each claim, and whether any pre-existing condition in your file was ever actually disabling.
None of that is visible from an examining room, and none of it is a physician’s job to weigh. It is a conversation to have with your attorney before anyone puts a percentage in a report — not so that anyone shades an opinion, but so that you understand what the answer means for you before it is given.
What is worth your attention
With two claims close together and overlapping body parts, these questions usually move the case more than the apportionment percentage does:
- Are both claims established for the right sites and conditions, or is one narrower than your treatment actually is?
- Is the causal relationship opinion consistent across the two files, or do the records say different things?
- Has maximum medical improvement genuinely been reached, or is the permanency workup early?
- Is the loss of wage earning capacity evidence developed — the vocational side, not just the medical percentage?
The same distinction decides whether diabetes reduces an award when a small injury at work becomes a serious one — covered on our page about puncture wounds and diabetic foot injuries.
Frequently Asked Questions
What is apportionment in a New York workers’ comp case?
Apportionment divides responsibility for one permanent condition among its causes, for example between two work injuries to the same body part, or between a work injury and an older condition.
Can my award be reduced because of an old injury that wasn’t work-related?
Generally not, if you were able to effectively perform your job despite the old condition. In schedule loss of use cases, apportionment may apply only if medical evidence shows the old injury would itself have resulted in a schedule loss of use. Courts have rejected it where there were no medical records showing measurable loss of use before the work accident.
I have two workers’ comp claims for the same body part. Does apportionment lower what I receive?
Usually not. Between two established claims, apportionment generally divides the cost between the claims and their carriers rather than reducing your award.
Does my doctor have to address apportionment?
Generally, your doctor is not required to address it. But how the medical reports treat your claims, and any earlier injury, can matter a great deal, so it is worth discussing with your attorney before the permanency stage.
Could apportionment ever help me?
Yes. Limits on how long classification benefits can be paid apply only to accidents on or after March 13, 2007. If you have one claim before that date and one after, shifting more of the permanent disability to the older claim can matter. That is why it helps to know which answer works for you before the question comes up.
Talk to a New York workers’ compensation attorney
Two claims running together is one of the situations where having the same attorney handle both files matters, because the two records have to tell one consistent story. Workers’ Compensation Board hearings in New York are held virtually, so we represent injured workers throughout the state, not only in Staten Island and Brooklyn.
Consultations are free. If we don’t recover money for you, we don’t get paid. Call 718.701.2776.
This article is general information about New York workers’ compensation procedure. It is not legal advice, and reading it does not create an attorney-client relationship. Every claim turns on its own medical record and its own history. Attorney Advertising.
