Personalis Has One Counterparty in Three Different Jobs

Natera (NTRA) occupies three seats in Personalis (PSNL)’s filing: customer, partner, and competitor. That is the sharpest knot in a relationship map otherwise spread across drugmakers, diagnostics companies, and one very important equipment supplier.

Personalis says a small group of customers supplies a large share of its business.

"We have substantial customer concentration, with a limited number of customers accounting for a substantial portion of our revenue and accounts receivable; in particular, we currently derive a substantial portion of our revenue from three of our largest…"

Personalis / SEC filing / May 7, 2026

In plain English, the customer base is not a democratic institution. Personalis also reported first-quarter 2026 revenue of $15.5 million, down 25% year over year, citing lower revenue from pharma testing services and other customers. The supplied disclosure does not assign that decline to any one named customer.

Natera is not merely buying from Personalis. It is also using Personalis’ tumor-analysis work in its own test, with the partnership carrying an unusually large share of one revenue category.

"Revenue from our partnership with Natera to provide advanced tumor analysis for use in Natera's MRD test currently makes up substantially all of the revenue in this category."

Personalis / SEC filing / August 5, 2025

That makes Natera a disclosed customer and commercial partner at the same time. Personalis also names Natera among its present or potential competitors, so the relationship has a third label: rival.

"Some of our present or potential competitors, including Adela, Inc., Caris Life Sciences, Inc., DELFI Diagnostics, Inc., Exact Sciences Corporation, which was acquired by Abbott Laboratories, Inc., in March 2026, Foresight Diagnostics Inc. (“Foresight”)…"

Personalis / SEC filing / May 7, 2026

The competitor list also includes Caris Life Sciences (CAI), GRAIL (GRAL), Guardant Health (GH), Quest Diagnostics (DGX), and Myriad Genetics (MYGN). The reverse map adds Veracyte (VCYT): its filing names Personalis as a competitor. So does Guardant, Caris, Natera, and Tempus AI (TEM). In this market, a company can apparently send a purchase order and appear on the other side of the competitive fence.

Tempus is another two-lane relationship. Personalis says Tempus can market its NeXT Personal test to physicians and pharmaceutical customers, while Tempus’ own filing names Personalis as a competitor.

"We also have a collaboration with Tempus that enables Tempus to market our NeXT Personal ® Dx test to physicians for breast cancer, lung cancer, colorectal cancer and immuno-oncology monitoring, and to market and sell NeXT Personal to Tempus' pharmaceutical…"

Personalis / SEC filing / May 7, 2026

The drugmaker ties are broader than a single customer order. Personalis says it provides genomic testing to Moderna in clinical trials for a personalized cancer therapy, and identifies strategic alliances with Moderna and Merck. A separate Merck investment agreement links the companies to a planned laboratory funded in part by reserved proceeds.

"Pursuant to the terms of the Merck Investment Agreement, the Company agreed to reserve $ 10.0 million of the proceeds to open an ISO-certified laboratory in a region outside of the United States, with such region mutually agreed upon by the Company and Merck."

Personalis / SEC filing / February 26, 2026

Then there is Illumina (ILMN), the cleanest supplier dependency in the filing. Personalis names Illumina as its sole supplier of sequencers, reagents, and other materials used in routine laboratory operations, as well as the sole provider of maintenance and repair services for those sequencers.

"For example, we rely on Illumina as our sole supplier of sequencers and various associated reagents and other materials used in our routine laboratory operations, and as the sole provider of maintenance and repair services for these sequencers."

Personalis / SEC filing / May 7, 2026

The map, then, has a distinct shape: Natera is buyer, partner, and competitor; Tempus is collaborator and competitor; Merck is customer, alliance partner, and investment-agreement counterparty; and Illumina sits alone on the disclosed sequencing-supply line.

These are relationships disclosed in SEC filings, mapped by jodie’s analytics. This is not investment advice.