Chapter 4 4.5

Buybacks and Debt Management

MOF buyback operations, switch auctions, and liability management exercises

Beyond Issuance: MOF Liability Management

📝 Terminology Note: In Japanese market parlance, buyback operations are commonly referred to as rinban (輪番) or more formally rinban operations (輪番オペレーション). This term is used interchangeably with "buyback operations" in trader conversations and BOJ/MOF communications. While technically "rinban" originally referred to BOJ's regular bond purchase operations for monetary policy, the term has evolved to encompass both BOJ purchases and MOF buybacks in casual market usage.
  • MOF Buybacks (国債買入): Debt management tool
  • BOJ Rinban (輪番): Monetary policy tool (QE/QQE)
  • Market Usage: "Rinban" often used for both, distinguished by context

The Ministry of Finance (MOF) doesn't just issue new debt; it actively manages its own outstanding debt portfolio. This "liability management" has two primary goals:

  1. Smooth the "Redemption Cliff": Avoid having too much debt mature at one time, which would force the MOF to issue a massive amount of "refunding bonds" and risk a failed auction.
  2. Enhance Market Liquidity: Buy back older, illiquid bonds ("off-the-runs") to provide an exit for investors and keep the market functioning smoothly.

The MOF's main tools for this are Outright Buybacks and Switch Auctions.


MOF Buyback Operations: Three Types

1. Outright Buyback Operations (国債買入)

What It Is:

The MOF offers to buy back specific, older JGBs for cash—essentially a reverse auction where the government buys instead of sells.

Purpose:

  • Primary Goal: Enhance market liquidity for off-the-run bonds
  • Secondary: Reduce outstanding debt in specific maturity buckets

Mechanism:

  1. MOF announces a buyback auction for specific maturity ranges (e.g., "JGBs maturing in 5-10 years")
  2. Target amount: ¥300-800 billion typical
  3. Investors submit offers (prices at which they'll sell to the MOF)
  4. MOF accepts lowest price offers first (cheapest for government)
  5. Settlement: T+1, cash paid via BOJ-NET

Worked Example: Outright Buyback Operation

Scenario (February 2025):

  • MOF announces buyback of ¥500 billion of JGBs maturing in 7-10 years
  • Target: Off-the-run bonds with low liquidity in secondary market
  • Auction Date: February 15, 2025

Eligible Bonds & Offers Submitted:

Bond Maturity Seller Price Offer Amount (¥B) Status
JGB #350 Mar 2032 Mitsubishi UFJ ¥98.50 ¥200 ✅ Accepted
JGB #355 Jun 2033 Nomura ¥99.20 ¥150 ✅ Accepted
JGB #362 Sep 2031 SMBC Nikko ¥100.10 ¥150 ✅ Accepted (Stop)
JGB #368 Dec 2034 Daiwa ¥101.50 ¥100 ❌ Rejected
Total Accepted: ¥500 billion (target met)
Stop Price: ¥100.10 (highest accepted offer)
MOF Cash Outlay: (200B × ¥98.50/100) + (150B × ¥99.20/100) + (150B × ¥100.10/100) = ¥495.9 billion

Why It Works: Banks holding illiquid JGB #350 can now exit at ¥98.50, reinvest the cash into liquid on-the-run bonds. The MOF retires ¥500B of debt early, reducing future redemption pressure.

2. JGB Switch Operations (国債借換)

What It Is:

A simultaneous operation where the MOF buys back one set of bonds and sells (issues) another set—essentially swapping old debt for new debt with different maturities.

Purpose:

  • Maturity Extension: Push redemptions further into the future
  • Debt Smoothing: Avoid large redemption cliffs
  • Cash Neutral: No net increase in outstanding debt

Worked Example: Switch Operation (Maturity Extension)

Problem:

The MOF forecasts a massive ¥15 trillion redemption spike in fiscal year 2027 (bonds issued during the 2017 stimulus program). This creates refinancing risk—if yields spike in 2027, the government faces high borrowing costs.

Solution: Switch Operation (April 2025)

Step 1: Buyback Component

  • MOF buys back ¥800 billion of JGBs maturing in 2027-2028
  • Average buyback price: ¥99.50 per ¥100
  • Cash Outlay: ¥796 billion

Step 2: Issuance Component (Simultaneous)

  • MOF sells ¥800 billion of new 20-year JGBs (maturing 2045)
  • Auction results: Average price ¥100.20 per ¥100
  • Cash Received: ¥801.6 billion
Net Cash Impact: ¥801.6B (received) - ¥796B (paid) = +¥5.6B surplus
Maturity Profile Change:
  • FY2027 redemptions: -¥800B (reduced)
  • FY2045 redemptions: +¥800B (new liability)
Result: Redemption cliff smoothed by 18 years, operation profitable due to upward-sloping yield curve

Why The MOF Profits: In a normal upward-sloping yield curve, short-term bonds trade at premium (¥99.50) while long-term bonds can be issued near par (¥100.20). The MOF captures the positive carry of extending maturity.

3. Buybacks for Maturity Shortening ("Pre-funding" / 短期前倒し買入)

What It Is:

Using surplus cash (from tax revenues or budget surplus) to buy back bonds that mature within the next 1-3 years, reducing the need for refunding auctions.

Purpose:

  • Smooth redemption spikes at the front end of the curve
  • Reduce rollover risk in money markets
  • Utilize temporary cash surpluses efficiently

Worked Example: Pre-funding Buyback

Scenario (December 2024):

  • FY2024 tax revenues exceed budget projections by ¥1.2 trillion
  • ¥5 trillion of 5-year JGBs scheduled to mature in March 2025
  • MOF faces refinancing pressure: must issue ¥5T in new bonds to pay off maturing bondholders

Pre-funding Action:

  • MOF uses ¥1.2T surplus cash to buy back JGBs maturing March 2025
  • Buyback price: ¥99.95 (near par, since bond matures in 3 months)
  • Amount retired: ¥1.2 trillion
Before Pre-funding: March 2025 redemption = ¥5.0 trillion
After Pre-funding: March 2025 redemption = ¥3.8 trillion
Refunding Auction Size: Reduced from ¥5.0T → ¥3.8T
Benefit: 24% smaller auction, lower market impact, reduced rollover risk

Market Impact: Smaller refunding auctions reduce supply pressure, supporting JGB prices. Bondholders receive early redemption at favorable prices. The operation signals fiscal discipline (using surpluses to reduce debt).

💡 Key Distinction: MOF vs. BOJ Operations
  • MOF Buybacks: Debt management tool to smooth redemptions and enhance liquidity. Funded by budget/cash reserves.
  • BOJ Rinban: Monetary policy tool (QE/YCC). BOJ buys ¥5-7 trillion/month to suppress yields. Funded by creating bank reserves (money printing).
  • Net Effect: Both reduce JGBs in circulation, but MOF retires debt permanently while BOJ holds it on balance sheet.

Together, these operations allow the MOF to act as a "steward" of the JGB market, not just an issuer. They fine-tune the maturity profile of Japan's massive ¥1,000+ trillion debt and ensure that even decades-old bonds remain liquid.


References

  1. Japan Ministry of Finance. "JGB Buy-back and JGB-Switching Programs." *Debt Management Report 2022, Chapter 2*. Available at: https://www.mof.go.jp/english/policy/jgbs/publication/debt_management_report/2022/esaimu2022-2-2.pdf.