SELLAS Life Sciences Group, Inc.

SLSNASDAQHealthcare● Active

$7.98

$-0.25(-3.04%)

Market Cap$1.1B

P/E Ratio—

52W High$9.51

52W Low$1.39

Avg Volume7.9M

Open$8.51

Beta2.53

Employees Ownership Insider Trades

SELLAS Life Sciences Group, Inc. (SLS) Number of Employees – History & Annual Headcount

Annual SEC headcount, year-over-year change, and per-employee efficiency — chart and full history below.

SEC EDGAR · FMP · SLS · as of Mar 19, 2026

Latest filing snapshot

-2-13.33%vs prior year

SELLAS Life Sciences Group, Inc. (SLS) employee data is sourced from the annual SEC 10-K filing. As of 2025, full-time employees only. Global consolidated headcount. View SEC filing ↗

SEC 10-K·Period end: 2025-12-31·Full-time · Global

Total Employees

Change (1Y)

-2

Growth % (1Y)

-13.33%

Revenue / Employee

—

Net Income / Employee

$-2.07M

Market Cap

$1.1B

SLS Employee Count

2007 – 2025 · Annual · SEC filing

Source: SEC annual filings · Hover bar to view year data · Click to view original filing

Employees History

Filing Date	Period End	Employees	Change (1Y)	Growth (1Y)
2026-03-19	2025-12-31	13	-2	-13.33%
2025-03-20	2024-12-31	15	-1	-6.25%
2024-03-28	2023-12-31	16	-1	-5.88%
2023-03-16	2022-12-31	17	+6	+54.55%
2022-03-31	2021-12-31	11	+4	+57.14%
2021-03-23	2020-12-31	7	+2	+40.00%
2020-03-13	2019-12-31	5	-3	-37.50%
2019-03-22	2018-12-31	8	-3	-27.27%
2018-04-13	2017-12-31	11	-3	-21.43%
2017-03-15	2016-12-31	14	-8	-36.36%

▸ Source: SEC Annual Reports (Form 10-K / 20-F). Employee counts as of fiscal year end. Click the ↗ icon at the end of a row to open the original SEC filing in a new tab.

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SLS

SELLAS Life Sciences Group, Inc.YOU

13$1.1B

Source: /stock-peers + /profile.fullTimeEmployees · Click row → /employees · Sorted by headcount · SLS peer comparison

About SLS employees

SLS Employees · Headcount

SELLAS Life Sciences Group, Inc. (SLS) employee data is sourced from the annual SEC 10-K filing. As of 2025, SELLAS Life Sciences Group, Inc. had 13 full-time employees globally. Full-time employees only. Global consolidated headcount.

SELLAS Life Sciences Group, Inc.'s workforce decreased by 2 (13.33%) in 2025 compared to the prior fiscal year. The historical trend reflects the company's expansion and contraction cycles.

Revenue Financial statements Net income SEC filings Price history Forecast & ratings Ownership Earnings

Frequently Asked Questions

SLS Employees · 5 questions

As of the latest SEC 10-K filing (2025), SELLAS Life Sciences Group, Inc. had 13 full-time employees globally. This figure is sourced from the company's mandatory annual disclosure to the SEC.

SELLAS Life Sciences Group, Inc. employee counthow many employees does SELLAS Life Sciences Group, Inc. haveSLS total employees 2025

▸ Data source: FMP /historical-employee-count · SEC EDGAR annual filings · As reported · Global consolidated headcount · As of 2026-03-19