Japan's Convertible Bond Issuance Hits 20-Year High
N.R. Finch
Japanese convertible bond issuance reached ¥1 trillion in the first half of 2026, the highest for any comparable period since 2004; the BOJ's rate-hiking cycle has pushed companies toward this low-cost hybrid instrument, but conversion-dilution risk is already hammering share prices.
Where did the ¥1 trillion come from?
Two mega-deals drove the total: Nippon Steel issued ¥600 billion — the largest single convertible in Japanese history — and JX Advanced Metals followed with ¥250 billion.
Demand far exceeded supply. Nippon Steel's book was oversubscribed "several times over"; JX Advanced Metals and Advantest each saw subscription ratios above eight times.
This means → institutional buyers are treating convertibles as a distinct asset class worth scaling into, not a one-off trade.
Why are companies suddenly drawn to convertibles?
The catalyst is interest rates. The BOJ ended negative rates in 2024 and in June hiked the benchmark to 1%, the highest since 1995. The 10-year JGB yield rose to levels not seen since 1996.
In plain terms = Japanese companies used to borrow at near-zero cost; now the interest bill has thickened, and they need a cheaper alternative.
Convertible bonds — hybrid instruments that let investors swap debt for equity if the share price rises — can be issued at zero or near-zero coupons. Advantest stated explicitly that its zero-coupon deal was designed to "minimize financing costs."
Daiki Arima, head of Japan ECM at J.P. Morgan, noted that some issuers are also embedding put-like early-redemption clauses to sweeten terms for investors.
Why did share prices drop instead?
The trade-off is dilution: once investors convert, total shares outstanding rise and earnings per share shrink.
The market response was swift — Nippon Steel's stock fell more than 5% after the announcement; JX Advanced Metals dropped roughly 17%.
This means → the company secures cheap funding, but existing shareholders immediately absorb the expected future dilution hit.
Advantest's countermeasure: setting the conversion price above the current market price, aiming to delay the window in which dilution actually kicks in.
Who benefits from high volatility?
The Nikkei 225 posted its largest quarterly gain on record in Q2, yet the volatility index stayed above its five-year average.
In plain terms = the market is rising but swinging hard — a combination that especially rewards convertible-arbitrage players, who trade the bond and the underlying stock simultaneously to capture volatility premiums.
This reflects a structural dynamic: high volatility is both a risk signal and an amplifier of the "option value" embedded in convertibles — the bigger the swings, the more the conversion right is worth, and the easier the bond sells.
Can the momentum last into the second half?
Hayato Takei, head of equity co-underwriting at Mizuho Securities, said proposals and discussions with corporates have "clearly increased" and expects the trend of convertibles as a key financing option to continue.
Cyril Batkin, a convertible and credit portfolio manager at Ellipsis Asset Management, currently holds Japan convertibles at 5% of his strategy and plans to raise that to roughly 10% — provided "more tech issuers come to market."
Daniel Lutz, senior portfolio manager at Holinger Asset Management, outlined three conditions: pricing discipline, sustained equity resilience, and issuers deploying proceeds to create shareholder value.
This means → the directional consensus is bullish, but whether the market evolves from "two mega-deal driven" to "regular-cadence issuance" hinges on all three conditions holding simultaneously in H2.
Content is for reference only, not financial advice.