The Framework

The Buffett–Graham screening methodology — exactly how we find deep value stocks

Graham built the system. Buffett refined it. Our AI runs it across 9,927 SEC-registered companies, three times a day. Here's every filter, threshold, and decision point.

A free guide from The Margin of Safety newsletter · 15 min read

Why a systematic framework beats intuition

The greatest investors in history didn't pick stocks on instinct. They built repeatable systems — specific criteria that a business had to meet before a single dollar was committed. The system removes emotion from the equation.

Buffett has described his investment process as running through a mental checklist. Graham codified his criteria so precisely that he could train students to apply them. The edge isn't in finding hidden information — it's in consistently applying a rational framework when most investors are acting emotionally.

What follows is our implementation of that framework — the exact filters our AI scanner runs on every company in the SEC database.

Stage 1 — The quantitative screen

Every company must pass all of these filters before advancing. These aren't guidelines — they're hard cutoffs. A company that fails any single filter is eliminated, regardless of how attractive it looks on other metrics.

Metric Threshold Why it matters
Return on Invested Capital (ROIC) > 10% Measures how efficiently the business creates value. Below 10% means the business is destroying economic value at the cost of capital.
Debt-to-Equity Ratio < 2.0 High leverage amplifies losses in downturns. Graham was adamant: a leveraged company has no margin of safety.
Free Cash Flow (TTM) Positive Earnings can be manipulated. Cash flow is harder to fake. We require positive FCF over the trailing twelve months.
Margin of Safety vs. DCF 28–38% (sector-adjusted) The price must be at least 28% below our intrinsic value estimate. Thresholds vary by sector volatility.
Exchange NYSE, NASDAQ, AMEX OTC and pink sheet stocks are excluded. Liquidity and disclosure requirements matter for fair valuation.
Beta Logged, not filtered We track beta for context but don't eliminate on it. High beta stocks trading at deep value can offer exceptional risk-adjusted returns.

Stage 2 — The DCF valuation

Companies that pass the quantitative screen receive a full discounted cash flow valuation. This is where we calculate intrinsic value — the number we compare against the current market price to determine the margin of safety.

How we build the DCF

We pull financial data from multiple sources: SEC EDGAR filings (the primary source, as reported directly to regulators), Yahoo Finance for market data, and Financial Modeling Prep for supplementary historical data. The DCF inputs are:

We don't use a single point estimate. We stress-test across three scenarios (bear/base/bull) and use the conservative case as our working intrinsic value. The margin of safety must hold even in the bear scenario.

Stage 3 — The LLM qualitative analysis

Numbers tell you what happened. SEC filings tell you why — and what management thinks will happen next. For every company that passes quantitative screening, our AI reads the most recent 10-K or 10-Q filing from EDGAR and evaluates:

1
Moat Assessment
Does the business have durable competitive advantages? Can competitors replicate what makes this company profitable? The AI looks for specific language around pricing power, customer retention, barriers to entry, and proprietary assets.
2
Red Flag Scan
Earnings restatements, going concern language, related-party transactions, auditor changes, significant litigation, covenant violations, customer concentration above 20%. Any major red flag triggers a downgrade.
3
Management Signal Analysis
What is management saying about the business trajectory? Are they guiding up or down? Is there insider buying or selling? Are capital allocation decisions rational — dividends, buybacks, or reinvestment at high ROIC?
4
Conviction Score (1–10)
The AI synthesizes all factors into a 1–10 conviction score. Only companies scoring 9 or 10 are classified as DEEP VALUE signals. Scores of 7–8 become WATCH signals. Below 7 are filtered out despite passing the quant screen.

What a real signal looks like

This is a representative example of a DEEP VALUE signal from our scanner — anonymized but based on a real output:

EXAMPLE
Mid-cap industrial manufacturer · NYSE
DEEP VALUE
Margin of Safety
47.3%
ROIC
18.4%
D/E Ratio
0.82
Conviction Score
9/10
FCF (TTM)
$124M
Beta
1.14
Moat: Proprietary manufacturing process with 15-year customer contracts. No material red flags. Management bought $2.1M in open market shares in Q4.

What the framework doesn't do

Transparency matters. Here's where our approach has known limitations:

On Honesty

"Knowing what you don't know is more useful than being brilliant." — Charlie Munger

How to use the signals

The signals are a starting point for your own research, not a replacement for it. When you receive a DEEP VALUE signal, we recommend:

  1. Read the most recent 10-K yourself — particularly the risk factors and MD&A sections
  2. Understand the industry dynamics and who the main competitors are
  3. Verify that you understand why the stock is trading at a discount (there's always a reason — is it temporary or structural?)
  4. Size your position appropriately — even high-conviction signals warrant position sizing discipline

The scanner surfaces the opportunity. The judgment call is still yours.

See the framework in action

The scanner runs three times a day. Free subscribers get the top signals every week — the highest-conviction outputs from 9,900+ company scans.

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