Federal regulators say Medicare has been overpaying for routine lab tests by roughly 16%. The two companies most exposed barely moved on the news.
The Centers for Medicare & Medicaid Services this week unveiled preliminary 2027 payment rates for routine laboratory testing that the agency says will save taxpayers an estimated $1 billion a year once fully phased in. CMS said Medicare has been paying private laboratories roughly 16% more than commercial insurers pay for the same tests, and that new rates will correct the gap gradually, subject to a statutory cap limiting any single year's cut to 15%, phasing in through 2029.
Quest Diagnostics and Labcorp, the two national laboratory chains that process the largest share of Medicare-reimbursed routine testing, were the companies most directly named in coverage of the announcement, though CMS's own release does not single out either company. The rates announced this week are preliminary: a 30-day public comment period is underway, a separate determination process for tests without private-payor pricing data is expected in early October, and CMS has said final 2027 rates won't be set until November.
The market's initial reaction looks smaller than the headline figure might suggest. Quest Diagnostics shares slipped 0.64% on the day CMS made its announcement, while Labcorp shares were essentially flat, up 0.09%. That muted response is consistent with a rule that phases in gradually and caps annual cuts at 15%, a materially different risk than an immediate, one-time reduction of that size would represent. It may also simply reflect that Wall Street hasn't yet finished modeling the change: detailed analyst estimates of the rule's per-share impact on either company have not yet circulated, and are expected to firm up only after the rates become final in November.
Neither Quest nor Labcorp has disclosed exactly what share of its revenue comes from Medicare-reimbursed routine testing specifically, which limits how precisely investors can size the eventual hit. What is clear is that CMS has now put a specific, gradual, capped mechanism in motion, and the real test for both stocks is likely to come not this week, but when the November final rule lands and the sell-side finally puts a number on it.