Compare StocksBIIB vs PFE

Biogen Inc. (BIIB) vs Pfizer, Inc. (PFE): Which Is the Better Buy in 2026?

As of 2026-08-03, BIIB is undervalued at $203, with a DCF intrinsic value of $897 and a margin of safety of 77%. PFE is undervalued at $25, with an intrinsic value of $127985960274 and a margin of safety of 100%. Of the two, PFE has the wider margin of safety.

BIIB
Biogen Inc.
$202.95
VS
PFE
Pfizer, Inc.
$25.01

Rewards

BIIB
  • Gross margin of 78.3% indicates strong pricing power — typical of businesses with significant intellectual property or brand strength.
  • Free cash flow has grown at a 19.9% CAGR over the past 4 years, demonstrating strong earnings power growth.
PFE
  • Gross margin of 74.8% indicates strong pricing power — typical of businesses with significant intellectual property or brand strength.
  • Trailing P/E of 19.1x is 37% below the historical average of 30.4x — potentially undervalued relative to its own history.

Risks

BIIB
  • FCF yield of 6.6% suggests reasonable valuation assuming continued moderate growth.
  • Trailing P/E of 36.1x is 83% above the historical average of 19.8x — the stock trades at a premium to its own history.
  • PEG ratio of 5.09 indicates the stock is expensive relative to its expected growth — the market may be pricing in more growth than analysts project.
PFE
  • ROIC has declined by 15.9 percentage points over the past 4 years, which may signal competitive erosion.
  • PEG ratio of 2.94 indicates the stock is expensive relative to its expected growth — the market may be pricing in more growth than analysts project.
  • Altman Z-Score of 1.38 places the company in the distress zone — financial patterns resemble those of companies that experienced bankruptcy.

Key Valuation Metrics

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BIIB
PFE
Valuation
$1.97B
Free Cash Flow
$12.38B
6.57%
FCF Yield
N/A
36.11
Trailing P/E
19.09
12.25
Forward P/E
8.85
Quality & Moat
7.30%
ROIC
10.19%
4.58%
ROE
8.31%
78.32%
Gross Margin
74.80%
5.09
PEG Ratio
2.94
Balance Sheet Safety
0.38
Net Debt / Equity
0.57
N/A
Interest Coverage
N/A
2.10
Net Debt / EBITDA
2.03
0.00%
Dividend Yield
6.88%
BIIB: 1Ties: 3PFE: 7
BIIBPFE

Historical Fundamentals

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BIIB

Price ÷ Earnings Per Share — how many years of current earnings you're paying for at today's price. Lower P/E may indicate undervaluation. The dashed forward point is the forward P/E — today's price ÷ analyst consensus EPS.

PFE

Price ÷ Earnings Per Share — how many years of current earnings you're paying for at today's price. Lower P/E may indicate undervaluation. The dashed forward point is the forward P/E — today's price ÷ analyst consensus EPS.

Price ÷ Earnings Per Share — how many years of current earnings you're paying for at today's price. Lower P/E may indicate undervaluation. The dashed forward point is the forward P/E — today's price ÷ analyst consensus EPS.

$1 Retained Earnings Test

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BIIB
$-3.44
created per $1 retained over 3 years
Market Cap Declined
Σ Retained
$4.09B
Δ Market Cap
$-14.04B
Buffett's "$1 Test": For every $1 of earnings retained, has management created at least $1 of market value?
> $1 created per $1 retained = Value Creator · < $1 created = Value Destroyer
PFE
N/A
Net losses over 3 years — test not applicable
Company had negative cumulative retained earnings
Σ Retained
$-10.61B
Δ Market Cap
$-26.34
Buffett's "$1 Test": For every $1 of earnings retained, has management created at least $1 of market value?
> $1 created per $1 retained = Value Creator · < $1 created = Value Destroyer

Buffett's "$1 Test": For every $1 of earnings retained, has management created at least $1 of market value?
> $1 created per $1 retained = Value Creator · < $1 created = Value Destroyer

Discounted Cash Flow (DCF) Analysis

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BIIB
77.4% Margin of Safety
Price is 77.4% below estimated fair value
Current Price: $202.95
Fair Value: $896.68
Strongly undervalued
Undervalued
Fairly valued
Overvalued
Strongly overvalued
PFE
100.0% Margin of Safety
Price is 100.0% below estimated fair value
Current Price: $25.01
Fair Value: $127985960274.09
Strongly undervalued
Undervalued
Fairly valued
Overvalued
Strongly overvalued

Reverse DCF — Market-Implied Growth

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BIIB

What growth rate is the market pricing in at $203?

+7.8%
Market-Implied Owner Earnings Growth
Standard FCF implies +6.9%

The market implies +7.8% Owner Earnings growth, above historical trends.

Standard FCF implies a demanding +6.9%, reflecting heavy growth investment.

PFE

What growth rate is the market pricing in at $25?

-14.2%
Market-Implied Owner Earnings Growth
Standard FCF implies -15.0%

The market implies -14.2% Owner Earnings growth, above historical trends.

Standard FCF implies a demanding -15.0%, reflecting heavy growth investment.

Economic Moat Score

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BIIB
55/100
Narrow Moat
70+ Wide · 40-69 Narrow · <40 None

Narrow moat with margin stability as the key competitive advantage. Improving roic consistency would strengthen the moat.

Composite score measuring competitive advantage durability across four dimensions: returns above cost of capital, pricing power stability, revenue predictability, and capital efficiency. Based on 5 years of fundamental data.
PFE
35/100
No Moat
70+ Wide · 40-69 Narrow · <40 None

No durable moat detected, though reinvestment efficiency shows some competitive positioning. The business lacks consistent evidence of sustainable advantages.

Composite score measuring competitive advantage durability across four dimensions: returns above cost of capital, pricing power stability, revenue predictability, and capital efficiency. Based on 5 years of fundamental data.

Forensic Accounting

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BIIB
-2.64
Unlikely Manipulator
Above -1.78 = likely manipulator · -2.22 to -1.78 = grey zone

M-Score Trend

Beneish's 8-variable model estimates the probability of earnings manipulation. An M-Score above -1.78 signals elevated risk — companies in this range have historically been 3-5× more likely to be manipulating earnings. Scores between -2.22 and -1.78 fall in a grey zone warranting further investigation.
PFE
-2.53
Unlikely Manipulator
Above -1.78 = likely manipulator · -2.22 to -1.78 = grey zone

M-Score Trend

Beneish's 8-variable model estimates the probability of earnings manipulation. An M-Score above -1.78 signals elevated risk — companies in this range have historically been 3-5× more likely to be manipulating earnings. Scores between -2.22 and -1.78 fall in a grey zone warranting further investigation.

Beneish's 8-variable model estimates the probability of earnings manipulation. An M-Score above -1.78 signals elevated risk — companies in this range have historically been 3-5× more likely to be manipulating earnings. Scores between -2.22 and -1.78 fall in a grey zone warranting further investigation.

Ownership Breakdown

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BIIB
Insiders 0.2%Institutions 96.4%Retail & Other 3.5%
No. of Institutional Holders1,468
High insider ownership aligns management incentives with shareholders — a key signal in Buffett-style analysis. Institutional concentration can indicate smart-money conviction but also crowding risk.
PFE
Insiders 0.1%Institutions 69.5%Retail & Other 30.4%
No. of Institutional Holders3,661
High insider ownership aligns management incentives with shareholders — a key signal in Buffett-style analysis. Institutional concentration can indicate smart-money conviction but also crowding risk.

High insider ownership aligns management incentives with shareholders. Institutional concentration can indicate smart-money conviction but also crowding risk.

Insider Buying Activity

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BIIB
0
Buys (3M)
1
Buys (12M)
Total value (12M): $585.00
MURPHY NICOLE
Officer
$585.00
@ $195.00 · 2026-02-12
DORSA CAROLINE D
Director
$151,559
@ $122.72 · 2025-05-02
Open market purchases · includes direct & indirect ownership · excludes option exercises
PFE
0
Buys (3M)
0
Buys (12M)
BLAYLOCK RONALD E
Director
$499,072
@ $25.65 · 2025-02-13
GOTTLIEB SCOTT
Director
$28,240
@ $28.24 · 2024-10-30
Open market purchases · includes direct & indirect ownership · excludes option exercises

Open market purchases · includes direct & indirect ownership · excludes option exercises.

Insider Selling Activity

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BIIB
0
Sells (3M)
3
Sells (12M)
Total value (12M): $734,709
SINGHAL PRIYA
Officer
$531,548
@ $199.83 · 2026-02-09
SINGHAL PRIYA
Officer
$134,116
@ $179.30 · 2026-02-02
SINGHAL PRIYA
Officer
$69,045
@ $133.55 · 2025-09-02
IZZAR RACHID
Officer
$300,105
@ $135.00 · 2025-07-08
SINGHAL PRIYA
Officer
$480,508
@ $126.25 · 2025-05-19
SHERWIN STEPHEN A
Director
$1.31M
@ $150.02 · 2025-03-07
SINGHAL PRIYA
Officer
$17,293
@ $157.21 · 2024-12-09
SINGHAL PRIYA
Officer
$88,019
@ $204.22 · 2024-09-03
Direct ownership only · excludes indirect, option exercises, planned (10b5-1) sales & derivatives
PFE
1
Sells (3M)
1
Sells (12M)
Total value (12M): $51,400
DAMICO JENNIFER B.
Officer
$51,400
@ $25.70 · 2026-06-09
DAMICO JENNIFER B.
Officer
$64,825
@ $25.93 · 2025-03-04
DAMICO JENNIFER B.
Officer
$147,714
@ $28.66 · 2024-08-13
Direct ownership only · excludes indirect, option exercises, planned (10b5-1) sales & derivatives

Direct ownership only · excludes indirect, option exercises, planned (10b5-1) sales & derivatives.

🎭 Mr. Market's Mood

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BIIB
FearGreed
😐Neutral(54/100)

"Market is pricing this stock without strong emotion in either direction"

Composite sentiment score based on 6 market signals. Inspired by Buffett's "Mr. Market" allegory — fear = potential opportunity, greed = potential risk. Must be used alongside fundamental analysis, not in isolation.
PFE
FearGreed
😐Neutral(52/100)

"Market is pricing this stock without strong emotion in either direction"

Composite sentiment score based on 6 market signals. Inspired by Buffett's "Mr. Market" allegory — fear = potential opportunity, greed = potential risk. Must be used alongside fundamental analysis, not in isolation.

Composite sentiment score based on market signals. Inspired by Buffett’s "Mr. Market" allegory — fear = potential opportunity, greed = potential risk. Must be used alongside fundamental analysis, not in isolation.

⚖️ Buffett Signal

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BIIB
Awaiting DCF Data

The Buffett Signal cross-references market sentiment with DCF valuation. Configure the DCF Analysis above to generate a signal.

DCF Margin of Safety: N/AMr. Market's Mood: Neutral (54)
PFE
Awaiting DCF Data

The Buffett Signal cross-references market sentiment with DCF valuation. Configure the DCF Analysis above to generate a signal.

DCF Margin of Safety: N/AMr. Market's Mood: Neutral (52)
View BIIB Full AnalysisView PFE Full Analysis

Frequently Asked Questions: BIIB vs PFE

Is Biogen Inc. or Pfizer, Inc. more undervalued in 2026?

Based on our discounted cash flow model, PFE trades at a 100.0% margin of safety (intrinsic value $127985960274 vs. price $25), compared to BIIB's 77.4% margin of safety (intrinsic $897 vs. $203).

Which stock has a wider economic moat, Biogen Inc. or Pfizer, Inc.?

BIIB scores 55/100 (Narrow moat), while PFE scores 35/100 (None moat). The moat score measures competitive advantage durability across ROIC consistency, margin stability, revenue predictability, and reinvestment efficiency.

Is Pfizer, Inc. in financial distress?

PFE's Altman Z-Score of 1.4 places it in the Distress zone, signaling elevated bankruptcy risk. BIIB scores 3.2 (Safe zone). The Altman Z-Score is a five-factor model that predicts insolvency within two years; scores below 1.81 indicate significant distress.

Which stock has higher return on invested capital, Biogen Inc. or Pfizer, Inc.?

PFE earns 10.2% ROIC versus BIIB's 7.3%. A higher ROIC means the company generates more profit per dollar of capital employed, a hallmark of durable competitive advantage in Buffett-style analysis.

BIIB vs PFE: Which Is the Better Buy in 2026? | SafetyMargin.io