Biogen Inc. bonds BIIB
Who owns Biogen Inc.'s debt and what their own filings say it is worth. Bond prices and yields are fund-reported marks (SEC Form N-PORT) as of Jul 2026; they lag the market by about two months. BIIB stock page.
Every bond funds hold
Each bond's latest fund-reported mark. Price per 100 of face value; yield to maturity from price, coupon and maturity; spread over the matched-maturity Treasury for US-dollar bonds.
| Bond | Coupon | Maturity | Ccy | Price | Yield | Spread | Funds | Held | As of |
|---|---|---|---|---|---|---|---|---|---|
| 09062XAH6 | 2.25% fixed | 2030-05-01 | USD | 90.76 | 4.98% | 69 bp | 22 | $100.7M | Jul 2026 |
| 09062XAN3 | 5.05% fixed | 2031-01-15 | USD | 100.55 | 4.91% | 60 bp | 10 | $19.0M | Jul 2026 |
| 09062XAL7 | 5.75% fixed | 2035-05-15 | USD | 102.36 | 5.41% | 86 bp | 12 | $8.6M | Jul 2026 |
| 09062XAD5 | 5.2% fixed | 2045-09-15 | USD | 89.17 | 6.17% | 111 bp | 6 | $3.2M | Jul 2026 |
| 09062XAG8 | 3.15% fixed | 2050-05-01 | USD | 62.42 | 6.19% | 108 bp | 9 | $2.8M | Jul 2026 |
| 09062XAK9 | 3.25% fixed | 2051-02-15 | USD | 62.33 | 6.28% | 117 bp | 4 | $911K | Jul 2026 |
| 09062XAM5 | 6.45% fixed | 2055-05-15 | USD | 102.28 | 6.28% | 118 bp | 6 | $1.7M | Jul 2026 |
Spread history
Median spread of the US-dollar bonds over Treasuries, month-ends with complete filings. Fund-reported.
Price history
Median fund-marked price across the bonds, per 100 of face value.
By month
Funds file on staggered quarter-ends, so each month-end is marked by the funds that reported for it; the amount held moves with which funds filed, not only with buying and selling.
| Month-end | Bonds | Held | Median price | USD yield | USD spread | Most funds on one bond |
|---|---|---|---|---|---|---|
| Jul 2026 | 7 | $137.0M | 90.76 | 6.17% | 108 bp | 22 |
| Jun 2026 | 7 | $240.5M | 92.67 | 5.84% | 92 bp | 35 |
| May 2026 | 7 | $271.9M | 92.23 | 5.88% | 89 bp | 32 |
| Apr 2026 | 7 | $142.7M | 91.48 | 5.99% | 114 bp | 21 |
| Mar 2026 | 7 | $235.4M | 91.31 | 6.08% | 126 bp | 37 |
| Feb 2026 | 7 | $235.2M | 93.60 | 5.75% | 107 bp | 34 |
| Jan 2026 | 7 | $129.9M | 92.30 | 5.86% | 108 bp | 20 |
| Dec 2025 | 7 | $247.9M | 92.03 | 5.88% | 110 bp | 35 |
| Nov 2025 | 7 | $221.2M | 93.99 | 5.71% | 105 bp | 33 |
| Oct 2025 | 7 | $143.5M | 92.65 | 5.79% | 117 bp | 21 |
| Sep 2025 | 7 | $292.4M | 92.28 | 5.86% | 113 bp | 32 |
| Aug 2025 | 7 | $232.5M | 91.02 | 6.12% | 127 bp | 33 |
| Jul 2025 | 7 | $142.5M | 89.71 | 6.12% | 120 bp | 19 |
Who holds the debt
Fund series in their latest quarterly N-PORT report, largest first, with the change in face value against each fund's own previous report. Names as reported in the filings. 50 added, 31 cut, 4 new holders and 7 exits in the latest quarter.
| Fund series | Report | Face value | Value | Change in face value |
|---|---|---|---|---|
| VANGUARD TOTAL BOND MARKET INDEX FUND VANGUARD BOND INDEX FUNDS | 2026-06-30 | $77.2M | $60.7M | $1.1M |
| VANGUARD TOTAL BOND MARKET II INDEX FUND VANGUARD BOND INDEX FUNDS | 2026-06-30 | $70.8M | $59.2M | $0 |
| Core Fixed Income Fund Principal Funds, Inc | 2026-07-31 | $65.0M | $59.0M | $0 |
| JPMorgan Core Plus Bond ETF J.P. Morgan Exchange-Traded Fund Trust | 2026-05-31 | $29.8M | $29.7M | $25.8M |
| iShares iBoxx $ Investment Grade Corporate Bond ETF iShares Trust | 2026-05-31 | $32.0M | $26.0M | $6.1M |
| iShares Core U.S. Aggregate Bond ETF iShares Trust | 2026-05-31 | $30.3M | $25.9M | -$395K |
| VANGUARD SHORT-TERM CORPORATE BOND INDEX FUND VANGUARD SCOTTSDALE FUNDS | 2026-05-31 | $23.1M | $21.1M | $1.7M |
| JPMorgan Core Plus Bond Fund JPMorgan Trust II | 2026-05-31 | $21.7M | $19.4M | $11.7M |
| VANGUARD INTERMEDIATE-TERM CORPORATE BOND INDEX FUND VANGUARD SCOTTSDALE FUNDS | 2026-05-31 | $16.9M | $17.6M | -$4.5M |
| DFA Investment Grade Portfolio DFA INVESTMENT DIMENSIONS GROUP INC | 2026-07-31 | $17.1M | $15.5M | $0 |
| VANGUARD LONG-TERM CORPORATE BOND INDEX FUND VANGUARD SCOTTSDALE FUNDS | 2026-05-31 | $16.7M | $13.3M | $4.7M |
| iShares Broad USD Investment Grade Corporate Bond ETF iShares Trust | 2026-05-31 | $13.0M | $11.0M | $200K |
| iShares 1-5 Year Investment Grade Corporate Bond ETF iShares Trust | 2026-05-31 | $11.1M | $10.3M | $150K |
| Fidelity U.S. Bond Index Fund Fidelity Salem Street Trust | 2026-05-31 | $9.7M | $10.0M | $0 |
| MFS Limited Maturity Fund MFS Series Trust IX | 2026-07-31 | $9.6M | $9.6M | $0 |
| Invesco BulletShares 2030 Corporate Bond ETF Invesco Exchange-Traded Self-Indexed Fund Trust | 2026-05-31 | $10.2M | $9.3M | $542K |
| Bramshill Income Performance Fund Advisor Managed Portfolios | 2026-06-30 | $13.3M | $8.7M | $0 |
| Calvert Short Duration Income Fund Calvert Fund | 2026-06-30 | $9.5M | $8.7M | $0 |
| JPMorgan Core Bond Fund JPMorgan Trust II | 2026-05-31 | $8.8M | $8.0M | $0 |
| LVIP Franklin Templeton Core Bond Fund LINCOLN VARIABLE INSURANCE PRODUCTS TRUST | 2026-06-30 | $8.6M | $7.9M | $0 |
| iShares Investment Grade Systematic Bond ETF iShares Trust | 2026-05-31 | $8.3M | $7.8M | -$396K |
| VANGUARD INTERMEDIATE-TERM BOND INDEX FUND VANGUARD BOND INDEX FUNDS | 2026-06-30 | $7.4M | $7.7M | $655K |
| iShares iBonds Dec 2030 Term Corporate ETF iShares Trust | 2026-07-31 | $8.4M | $7.6M | $472K |
| iShares Core Universal USD Bond ETF iShares Trust | 2026-07-31 | $9.1M | $7.6M | $1.9M |
| Touchstone Strategic Trust-Touchstone Flexible Income Fund Touchstone Strategic Trust | 2026-06-30 | $11.5M | $7.5M | $0 |
Largest exits in the latest quarter (fund held the bonds in its previous report, none now): Global X Investment Grade Corporate Bond ETF ($1.7M), Destinations Core Fixed Income Fund ($284K), BNY Mellon Balanced Opportunity Fund ($235K), VictoryShares Corporate Bond ETF ($210K), Strategic Allocation: Moderate Fund ($79K), Strategic Allocation: Conservative Fund ($44K), Columbia Short Duration Bond ETF ($20K).
ETFs holding these bonds
From each ETF's own latest N-PORT report: the issuer's bonds as a share of the ETF's net assets. A holdings list, not a recommendation.
| ETF | Report | Bonds | Face value | Value | % of net assets |
|---|---|---|---|---|---|
| BND VANGUARD TOTAL BOND MARKET INDEX FUND | 2026-06-30 | 5 | $77.2M | $60.7M | 0.02% |
| JCPB JPMorgan Core Plus Bond ETF | 2026-05-31 | 4 | $29.8M | $29.7M | 0.24% |
| LQD iShares iBoxx $ Investment Grade Corporate Bond ETF | 2026-05-31 | 3 | $32.0M | $26.0M | 0.09% |
| AGG iShares Core U.S. Aggregate Bond ETF | 2026-05-31 | 7 | $30.3M | $25.9M | 0.02% |
| VCSH VANGUARD SHORT-TERM CORPORATE BOND INDEX FUND | 2026-05-31 | 1 | $23.1M | $21.1M | 0.04% |
| VCIT VANGUARD INTERMEDIATE-TERM CORPORATE BOND INDEX FUND | 2026-05-31 | 1 | $16.9M | $17.6M | 0.03% |
| VCLT VANGUARD LONG-TERM CORPORATE BOND INDEX FUND | 2026-05-31 | 4 | $16.7M | $13.3M | 0.14% |
| USIG iShares Broad USD Investment Grade Corporate Bond ETF | 2026-05-31 | 7 | $13.0M | $11.0M | 0.06% |
| IGSB iShares 1-5 Year Investment Grade Corporate Bond ETF | 2026-05-31 | 2 | $11.1M | $10.3M | 0.05% |
| BSCU Invesco BulletShares 2030 Corporate Bond ETF | 2026-05-31 | 1 | $10.2M | $9.3M | 0.37% |
| IGEB iShares Investment Grade Systematic Bond ETF | 2026-05-31 | 3 | $8.3M | $7.8M | 0.57% |
| BIV VANGUARD INTERMEDIATE-TERM BOND INDEX FUND | 2026-06-30 | 1 | $7.4M | $7.7M | 0.01% |
| IBDV iShares iBonds Dec 2030 Term Corporate ETF | 2026-07-31 | 1 | $8.4M | $7.6M | 0.23% |
| IUSB iShares Core Universal USD Bond ETF | 2026-07-31 | 7 | $9.1M | $7.6M | 0.02% |
| BSV VANGUARD SHORT-TERM BOND INDEX FUND | 2026-06-30 | 1 | $6.0M | $5.5M | 0.01% |
Default risk, three ways
Stock market: distance-to-default
Distance-to-default 7.29: safer than 68% of companies (64th percentile in Healthcare). Market-implied, prices to 2026-10-16, balance sheet 2026-06-30.
| Equity value | $34.52B |
| Debt barrier (short-term + ½ long-term debt) | $4.45B |
| Equity volatility (1 year) | 33.4% |
| Asset value / asset volatility (solved) | $38.78B / 29.7% |
| Risk-free rate (1-year Treasury) | 4.28% |
Bond market: priced-in odds
A 108 bp spread prices in about 1.8% a year of default odds (spread ÷ (1 − 40% recovery)). Fund-reported marks as of Jul 2026; the spread also pays for liquidity and risk premium, so this overstates actual defaults.
Accounts: Altman Z
Altman Z = 3.03 (latest balance sheet). A fundamentals cross-check; see methods for the variant used.
The stock side: 13F filings
What institutions report holding in BIIB's stock and options. Options are reported at the value of the underlying shares, not the premium paid; 13F lists long positions only, lags 45 days after quarter-end, and does not show whether puts hedge a stock position.
| Quarter-end | Stock holders | Stock value | Put managers | Puts (underlying value) | Call managers | Calls (underlying value) | Convertible holders |
|---|---|---|---|---|---|---|---|
| 2026-09-30 filings still arriving | 138 | $339.6M | 1 | $904K | 1 | $3.5M | 0 |
| 2026-06-30 | 1,027 | $29.99B | 28 | $473.2M | 33 | $674.6M | 0 |
| 2026-03-31 | 990 | $20.48B | 27 | $358.6M | 25 | $288.4M | 0 |
| 2025-12-31 | 980 | $23.59B | 30 | $452.6M | 32 | $714.0M | 1 |
| 2025-09-30 | 894 | $17.94B | 27 | $312.0M | 36 | $562.8M | 0 |
| 2025-06-30 | 849 | $15.90B | 26 | $329.2M | 27 | $370.8M | 0 |
Officials trading BIIB bonds
Sources: fund holdings and fund-reported marks from SEC Form N-PORT (published about 60 days after each month-end); 13F filings; House and Senate periodic transaction reports and OGE Form 278-T; Treasury yields from FRED. Findings from filings, not advice. How each number is computed.