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Shares outstanding, dilution and buybacks

A source-backed guide to how company share counts change—and where to inspect the filed evidence before drawing a conclusion.

Companies analysed
367
Filed source
Annual 10-K
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What a changing share count means

Shares outstanding are the company pieces held by investors. If the count rises, each existing share can represent a smaller fraction of the business; if it falls, net repurchases may increase each remaining share’s ownership. The direction alone is not a verdict: acquisitions, employee compensation, conversions, buybacks and reorganisations can all move the number.

This research view compares reported year-end common shares from annual filings. It excludes suspected split or reorganisation discontinuities from leaderboards and links every company back to its full filed history.

Largest latest-year share-count increases

CompanyLatest periodShares1-yearLong-run context
Capital One Financial Corporation (COF)2025-12-31625.1M+64.0%+36.2%
Omnicom Group Inc. (OMC)2025-12-31313.1M+59.4%+45.6%
Strategy Inc (MSTR)2025-12-31312.1M+27.0%+170.2%
Synopsys, Inc. (SNPS)2025-10-31186.0M+20.7%+21.9%
Insmed Incorporated (INSM)2025-12-31214.3M+19.4%+108.5%
Brown & Brown, Inc. (BRO)2025-12-31336.0M+17.5%+18.7%
Tesla, Inc. (TSLA)2025-12-313.75B+16.6%+30.2%
Pan American Silver Corp. (PAAS)2025-12-31421.8M+16.2%+100.2%
Intel Corporation (INTC)2025-12-314.99B+15.3%+22.9%
SiTime Corporation (SITM)2025-12-3126.3M+11.4%+53.3%
Welltower Inc. (WELL)2025-12-31696.5M+9.6%+66.9%
Circle Internet Group (CRCL)2025-12-31242.3M+8.9%+8.9%

Largest latest-year share-count reductions

CompanyLatest periodShares1-yearLong-run context
AerCap Holdings N.V. (AER)2025-12-31162.7M-12.9%-33.8%
First Citizens BancShares, Inc. (FCNCA)2025-12-3112.1M-11.5%-16.3%
Synchrony Financial (SYF)2025-12-31347.0M-10.6%-40.6%
HCA Healthcare, Inc. (HCA)2025-12-31224.6M-10.2%-33.8%
CF Industries Holdings, Inc. (CF)2025-12-31153.6M-9.6%-28.2%
Tapestry, Inc. (TPR)2025-06-30208.1M-9.6%-24.7%
General Motors Company (GM)2025-12-31904.0M-9.1%-35.4%
D.R. Horton, Inc. (DHI)2025-09-30294.5M-9.1%-19.1%
Equinor ASA (EQNR)2025-12-312.50B-8.3%-19.9%
Fortive Corporation (FTV)2025-12-31313.4M-8.1%-7.3%
Dollar Tree, Inc. (DLTR)2026-01-31198.5M-7.7%-14.9%
PayPal Holdings, Inc. (PYPL)2025-12-31920.0M-7.4%-21.5%

Check any company for dilution

Enter a ticker for the exact filed counts, dates, change and split-comparability warning.

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Method and limitations

Latest and comparison values use commonStockSharesOutstanding from cached annual balance sheets dated 2024 or later. A one-year change of 65% or more, or a five-year change of 200% or more, is labelled not directly comparable and left out of rankings because it may reflect a split, merger, spin-off, pre-listing base or reporting discontinuity. This is a screening signal, not proof of economic dilution and not investment advice.

Primary source: SEC EDGAR. See the full methodology or report a correction to support@stockportfolio.pro.

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