Medical testing company regulatory filing citing Pregnancy paper — SERA Prognostics, 2026-01-08
SERA PrognosticsSERA PrognosticsNASDAQ SERA
Filings SEC · Quote Google cited a paper published in Pregnancy as the basis for its claims in a regulatory filing submitted to the U.S. Securities and Exchange CommissionU.S. Securities and Exchange Commission
Regulator · Website. The company read the manner in which it wrote the paper and the actual scope of the paper in sequence. The stock price movement for one month after the filing was compared to past cases of the same type. This is a retrospective judgment written after knowing the results. The paper was read only up to the abstract.
The disclosure wrote the paper in the press release like this
When a U.S. listed company has something to inform shareholders, the report submitted to the Securities and Exchange Commission is called 8-K. The item numbers of the document submitted by SERA Prognostics on 2026-01-08 were 7.01 Reg FD disclosure and 9.01 financial statements · attached documents. The company cited a paper published in Pregnancy in the attached press release. The sentence citing the paper, copied verbatim from the original, is as follows.
EX-99.1 2 sera-ex99_1.htm EX-99.1 JANUARY 2026 We are redefining pregnancy care to reduce the burden of preterm birth This presentation contains forward-looking statements that involve substantial risks and uncertainties.
What readers should first look at is where the company placed the paper in the press release. Next, they should determine whether the paper supports the entire company claim or only part of it. To answer the latter question, one must read the full paper. This article, which only read the abstract, cannot provide an answer.
The scope of the paper discussed in the abstract is limited to this extent.
The paper's title is Neonatal impact of maternal biomarker screening for risk of preterm birth with targeted interventions (PRIME): A multicenter, randomized, controlled trial and it was published in Pregnancy on 2026-01-01. The authors' affiliations are Women's Cancer Center of Nevada · University of Kentucky · University of Virginia · Louisiana State University in Shreveport. The summary published at the beginning of the paper is called abstract. What this article read was only up to there. This paragraph was rewritten by a person after filtering a draft written by a machine reading the abstract through numerical comparison, so it is a different grade from a full-text reading and a verified reading.
A randomized trial measured the ratio of two proteins in maternal blood during mid-pregnancy to identify individuals at high risk of preterm birth, then combined progesterone, low-dose aspirin, and nurse telephone counseling. In 19 locations in the United States, singleton pregnant women were divided into a group that received care based on test results and a group that received usual care without knowledge of the results. The primary outcomes were a composite index of newborn illness or death and the length of newborn hospital stay, with gestational age and newborn intensive care unit admission also examined. The results are in the latter part of the abstract. This article does not include the part it has not read.
What the abstract does not answer remains in the full text and appendix. This article leaves gaps as gaps. Readers compare the two citations above to determine which sentence in the abstract the company cited.
One month later, the stock price was in the bottom quarter of the sample.
The remaining return after subtracting the portion that moves with the overall market is called excess return. Dates are counted in trading days, which are only the days the stock market is open. In terms of the calendar, 20 trading days are about a month. The excess return on the day of the regulatory filing and the following month are listed in the table below.
| Period | Excess return relative to the market | Meaning |
|---|---|---|
| 5 trading days before the filing | +10.2% | The extent of movement before the filing |
| On the filing date | +6.1% | On the filing date or the first trading day thereafter |
| Cumulative over +1 to +5 trading days | +4.4% | One week |
| Cumulative over +1 to +20 trading days | −30.0% | One month |
A bundle of past cases of the same type is called a sample. The position counted from the bottom is expressed as a percentile. The one-month excess return of −30.0% in this case is within the bottom quarter, at the 12% position from the bottom among 142 cases in the sample.
| Sample scale (20 trading days) | Tenth from the bottom | Fourth from the bottom | Median | Top 25% | Top 10% | This case |
|---|---|---|---|---|---|---|
| Excess return | −31.9% | −20.1% | −6.9% | +5.5% | +19.5% | −30.0% |
Half of the sample falls between the two central marks on the chart. One checks the chart to see whether this case lies within or outside the range. The sample collects cases where U.S.-listed companies cited papers in 8-K filings over the past decade. The company itself is excluded from the sample. The numbers listed here are historical facts, not rules applicable to future cases.
There is one additional case where the same company cited a paper in an 8-K filing, and it is included in the table below.
| Filing date | Journal of the cited paper | Excess return over one month |
|---|---|---|
| 2023-09-25 | medRxiv | +7.5% |
Documents issued by the company after the filing
After the filing date, the company issued three 8-K filings. Only the item numbers are listed. In 8-K filings without titles, the item numbers indicate the type of content. Whether it was an earnings announcement or a contract can be determined by the item number. The specific event is read in the original text of each link.
- 2026-03-18 8-K Item 2.02,9.01 — Earnings announcement · Financial statements · Attached documents
- 2026-05-06 8-K Item 2.02, 9.01 — Earnings Announcement · Financial Statements · Attached Documents
- 2026-06-01 8-K Item 5.02,9.01 — Officer·director changes · financial statements·attached documents
What this article does not answer
This article, which reads only abstracts, cannot answer what the paper reviewed, how it was done, or what it showed. How many times the paper cited by the company was cited afterward can be verified again through the OpenAlexOpenAlex
Data source · Website citation count. What will be seen next is whether the company's next 8-K again cites the same paper.
Explanation of terms
- 8-K
- A voluntary report submitted to the U.S. Securities and Exchange Commission when a listed company has something to inform shareholders. The type is indicated by item numbers such as earnings, contracts, and officer changes. All events in this article come from this document.
- Excess return
- The remainder obtained by subtracting the market's overall return from the stock's return. It is used to observe the company's unique movement after removing the portion attributable to the market's collective rise or fall.
- Trading day
- A date counting only the days when the stock market is open. Since weekends and holidays are excluded, 20 trading days correspond to approximately one calendar month.
- Sample and percentile
- A bundle of past cases of the same type is a sample, and the position from the bottom within it is expressed as a percentile. A percentile of 10 means that nine out of ten cases performed better than this case.
- Abstract
- A summary placed at the beginning of a paper. The author writes in a few sentences what was done, how it was done, and what results were obtained. Without reading the full text, details and limitations of the method cannot be known.