Why isn't reported SBC the same as real dilution?

GAAP stock-based-compensation expense includes the grant-date fair value of options that may never be exercised (out-of-the-money), RSUs that may be forfeited, and grants offset by buybacks. The bucket sort separates phantom SBC from real share-count change.

What is phantom dilution?

Stock-based compensation expense recognized on the income statement that does not translate into actual share-count increase — typically out-of-the-money options that expire worthless.

How do RSUs differ from options for dilution?

RSUs vest into shares regardless of share price, so they dilute on the vest schedule. Options only dilute if exercised; deep-out-of-the-money options often never are.

Why is the Lyft FY2025 example useful?

It illustrates a real public company where reported SBC was $322M but net share count actually declined — the buyback program more than offset the RSU vesting. Reported SBC told one story; reality told another.

SBC Reality Check (Phil's Framework)

Stop conflating GAAP SBC expense with real economic dilution.

Every public-company analyst treats stock-based compensation as a single number that hits the income statement and dilutes the share count. That framing is wrong. Out-of-the-money options are phantom dilution — they generate GAAP expense but will likely never be exercised. RSUs and ITM options are real future dilution — they vest and convert to shares regardless of price. Buybacks offset — cash spent retiring shares reduces actual share count. This tool sorts your company's SBC into those three buckets and tells you what the real share-count change is.

Bucket sort

Phantom / Real / Offset

ITM vs OTM

Option moneyness flag

Net Δshares

After buyback

GAAP vs real

$ SBC vs share dilution

STAGE 1 OF 4

Current stock price and options outstanding

From the most recent 10-K stock-compensation footnote: the weighted-average exercise price of options outstanding and the option count.

Current stock price

Recent close, or the price you want to evaluate moneyness against.

Weighted-avg option strike

From the 10-K SBC footnote — the "weighted-average exercise price" of options outstanding.

Options outstanding (millions)

Total option count from the 10-K rollforward. For mature companies this is often near zero (RSUs replaced options ~2015 onward).

STAGE 2 OF 4

RSUs and PSUs outstanding

RSUs (and PSUs at target) convert to shares regardless of stock price. They are real future dilution.

RSUs + PSUs outstanding (millions)

From the 10-K equity-award rollforward — unvested RSUs and PSUs combined. PSUs at target unless company discloses otherwise.

STAGE 3 OF 4

Recent buyback and GAAP SBC expense

Recent-year buyback share count (millions)

Shares actually retired in the most recent fiscal year. From the cash flow statement "Repurchases of common stock" / weighted-average price.

Recent-year GAAP SBC expense ($M)

Total stock-based compensation expense recognized for the year, from the cash flow statement.

STAGE 4 OF 4

Reality check — what your SBC actually dilutes

Real economic dilution (RSUs + ITM options)

—

Shares that will actually be issued. This is the number that matters for per-share economics.

Phantom dilution (OTM options)

—

Generates GAAP expense but won't be exercised at current price. Phantom unless stock rebounds materially.

Buyback offset

—

Shares actually retired.

Net change in share count (this year)

—

Buyback offset − real dilution from the current year's vest schedule. Negative = share count declined.

GAAP SBC vs real dilution (at S)

—

Difference between GAAP SBC expense and the $ value of real (RSU + ITM option) dilution. A large gap = a lot of phantom expense.

Options ITM or OTM?

—

The bucket sort — show the math

Phantom (OTM options)

—

Options whose strike exceeds current price. They contribute GAAP SBC expense but are unlikely to be exercised at the current price — they represent phantom dilution unless the stock rebounds materially.

Real (RSUs + ITM options)

—

RSUs vest regardless of price. ITM options will be exercised. Both convert to shares. This is the real dilution embedded in the SBC footnote.

Offset (buyback)

—

Shares retired with cash. This is the only thing that reduces share count. When the buyback exceeds vest delivery for the year, share count declines.

Detailed waterfall

LEARN THE FRAMEWORK · APPLY TO ANY 10-K

Cross-references — the Phil framework in print.

· CFO & Controller's Operating Guide — Ch 19 Stock-Based Compensation · SBC Reality Check section walks through the bucket sort with the Lyft worked example
· First Principles for Public-Company Analysis — Ch 5 SBC framework (referenced)
· Lyft Educational Case Study (referenced)
· Sibling tools: Black-Scholes · Lattice · Monte Carlo TSR · Intrinsic / RSU

Educational only · Not tax, legal, or accounting advice · Consult a qualified professional for ASC 718 compliance. This framework is an analytical lens for public-company investors and CFOs reviewing reported SBC; it is not a substitute for ASC 718 grant-date fair-value measurement, which always uses the appropriate valuation model. "Phantom" does not mean the GAAP expense is wrong — it means the future-dilution implication is overstated by mechanical SBC-as-dilution analysis.

Stop conflating GAAP SBC expense with real economic dilution.

Current stock price and options outstanding

RSUs and PSUs outstanding

Recent buyback and GAAP SBC expense

Reality check — what your SBC actually dilutes

Same subject. Four levels of depth.

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