TLDR:
Founder shares (sometimes “founders’ shares” or “founder stock”) are common stock issued to the founders of a company at or near incorporation, representing their initial equity ownership before any external financing. The structure and treatment of founder shares fundamentally shapes founder economics, tax outcomes, and cap-table evolution as the company grows and raises capital.
Standard Founder Share Structure
Modern startup founder shares typically follow this pattern: incorporation with low par value common stock (e.g., $0.0001 per share in Delaware), founders subscribe to large numbers of shares at incorporation (often 5-10 million each) at par value, founders sign Restricted Stock Purchase Agreements (RSPAs) imposing vesting schedules and company repurchase rights for unvested shares, founders file 83(b) elections with the IRS within 30 days to elect taxation at grant value (essentially zero) rather than vesting value (potentially substantial). This structure converts all future appreciation into capital gains.
Founder Vesting
Even founders typically subject themselves to vesting schedules: standard 4-year vesting with 1-year cliff (no vesting in year 1, monthly vesting thereafter), reverse vesting mechanism (founder owns shares from grant but company has repurchase right for unvested portion if founder leaves), single-trigger or double-trigger acceleration on change of control (most common: 50% single-trigger plus full double-trigger), and acceleration on termination without cause. Vesting protects co-founders if one leaves prematurely and is virtually universal in venture-backed deals.
Turkish “Kurucu Hisseleri”
The Turkish term “kurucu hisseleri” refers to a specific legal concept—not directly equivalent to founder shares in US sense. TTK Article 348 permits anonim şirket articles to grant founders special “kuruluş ayrıcalıkları” (founding privileges) in the form of profit participation rights or governance rights for founder shares—these are technical advantages beyond ordinary share ownership. In modern Turkish startup practice, founders typically hold ordinary shares (adi paylar) without statutory founding privileges, and the “founder shares” concept is used loosely to refer to the founders’ equity holdings. Foreign-style vesting and 83(b) treatment require careful adaptation to Turkish tax law—Türkiye has no direct 83(b) equivalent, and vesting tax treatment differs from US.