Structured Treasury Portfolios for Bond Proceeds: How the Ladder Works

A structured Treasury portfolio is a ladder of U.S. Treasury securities that a bond issuer owns outright, built so that maturities land on the dates the fund expects to pay out, with a money market allocation behind the ladder for draws that arrive faster than planned.

It is one of the investment options for bond proceeds: the structure where the issuer holds securities outright rather than holding a contract on a provider.

mGIC evaluates and competitively bids guaranteed investment contracts, full-flex repurchase agreements and structured Treasury portfolios, and sells none of them.

For a construction fund, the questions below are the ones finance directors and bond counsel ask about the structure.

Direct ownership vs an investment agreement

In a structured Treasury portfolio the issuer owns the securities directly, where a guaranteed investment contract or repurchase agreement gives it a contract claim on the provider; the fuller comparison of owned securities vs an investment agreement covers how the two forms differ on safety, liquidity and procurement.

Ownership changes the credit shape of the fund: the issuer's claim is on Treasury securities held in its own account, not on a provider's promise to pay, so a provider's downgrade does not reach the portfolio itself.

What provider exposure looked like in the last credit cycle comes from Ambac's own FY2008 Form 10-K, which reported that the November 5, 2008 Moody's downgrade of Ambac Assurance resulted in a significant amount of collateral being posted by its investment agreement and derivatives businesses, and that its investment agreement portfolio shrank as agreements were repaid.

Collateral and other contract terms are how investment agreements answer that exposure, and the credit protection page takes them up in detail.

Owned securities answer it differently: their value before maturity is a market price, which cuts both ways, because the price available on a forced sale date is not fixed in advance.

Term length carries a federal tax rule of its own: under section 149(g) of the Internal Revenue Code, as summarized in IRS Publication 4079, a bond is a hedge bond unless the issuer reasonably expects that 85% of spendable proceeds will be used within 3 years and that no more than 50% of proceeds is invested in nonpurpose investments whose yield is substantially guaranteed for 4 years or more.

Publication 4079 lists exceptions, including issues where 95% of proceeds are invested in non-AMT tax-exempt bonds, or where a 10%/30%/60%/85% spending schedule over 1/2/3/5 years is met together with payment of 95% of legal and underwriting costs within 180 days.

Whether a particular instrument's yield is substantially guaranteed for these purposes is a tax-law determination, and it is one of the places tax counsel sits in the middle of the structuring decision.

How the two structures weigh out on a particular fund is its own comparison, taken up in GIC vs Treasury ladder.

Matching maturities to the draw schedule

A structured Treasury portfolio works by placing a maturity on each date the fund expects to pay out, so cash arrives as draws are made and the balance in between stays invested.

The expected payout path is the fund's draw schedule, and GFOA recommends making certain that the drawdown of proceeds is planned and recorded and that the investment duration is no longer than the expected drawdown schedule.

GFOA's guidance on investing bond proceeds also recommends revisiting the draw schedule periodically and keeping records for the required period, which it describes as typically the life of the bonds plus three years.

The same expectations do federal work: Treasury Regulation §1.148-2(b) judges whether an issue consists of arbitrage bonds on the issuer's reasonable expectations as of the issue date, and an officer of the issuer responsible for issuing the bonds must certify those expectations in good faith, stating the facts and estimates that form the basis for them.

Under §1.148-2(b)(2), no certificate is required if no unspent gross proceeds are expected after the issue date, other than amounts in a bona fide debt service fund, or if the issue price of the issue does not exceed $1,000,000.

The certification is evidence of those expectations, and the regulation notes that it does not establish any conclusions of law.

Because the ladder is built around spending, the temporary periods rules bear on how long it can run; the temporary periods page covers how long proceeds can earn above the bond yield.

Where a draw date is fixed and known years out, the ladder can use zero-coupon pieces: TreasuryDirect explains that STRIPS split a fixed-principal Treasury note, bond or TIPS into separate zero-coupon pieces, each paying once at maturity, under 31 CFR 356.31.

A 10-year bond becomes 21 pieces, the minimum face amount to strip is $100 in $100 multiples, and stripping and reassembly happen only in the commercial book-entry system, not in TreasuryDirect.

Bills and floating rate notes cannot be stripped, so the zero-coupon end of a ladder comes from eligible fixed-principal securities.

The MSRB glossary describes STRIPS as having the economic and trading characteristics of a zero coupon bond, and the acronym stands for Separate Trading of Registered Interest and Principal Securities.

The money market sleeve for faster spend-down

The money market sleeve is the liquid balance that sits behind the ladder and pays draws that arrive earlier or larger than the maturities assumed.

mGIC describes structured Treasury portfolios as matched to anticipated cash needs with a money market fund allocation for faster-than-expected spend-down, which is this sleeve's job.

The New York Fed defines SOFR as a broad measure of the cost of borrowing cash overnight collateralized by Treasury securities; the SOFR page explains why it matters for bond funds.

Some issuers hold the liquid portion in their state pool instead: California's LAIF, for example, offers separate bond proceeds accounts that its Information Digest says require a Bond Application and the Official Statement, take a one-time deposit with no cap, and are set up with a monthly drawdown schedule.

Those accounts carry no minimum or maximum balance and close automatically at zero balance, where regular accounts stay open, and LAIF otherwise does not allow multiple accounts or subaccounts.

The LAIF digest says nothing about arbitrage yield restriction or rebate, so that analysis stays with the issuer and its bond counsel, and the LAIF page covers the pool itself.

Competitive bidding of the securities

The portfolio is bought through a competitive solicitation: bid specifications describe what is being priced, qualified providers submit bids, and the bids are compared on rate and non-rate terms.

That is a Bidding Agent's work, and mGIC's covers writing the bid specifications, soliciting qualified providers, managing questions, receiving bids and comparing them.

Pricing discipline matters because open-market securities purchases carry a fair-market-value question: in a settled SEC order dated April 6, 2000 (Securities Act Release No. 7826), the SEC described overcharging by dealers for open-market escrow securities in positive-arbitrage advance refundings as yield burning, called the practice illegal, and noted that the IRS can declare interest on the refunding bonds taxable.

Those findings concern refunding escrows rather than new construction funds; the specifications, the solicitation and the received bids document what the issuer was offered and what it paid.

Whether a purchase fits the fair-market-value safe harbor in the arbitrage rules is a question with several conditions, and the safe harbor page sets them out.

For escrows funded with open-market securities, GFOA describes an escrow bidding agent that solicits bids for the securities used in the escrow, and notes that a municipal advisor, if engaged, may be able to act as escrow bidding agent.

The same solicitation discipline is what mGIC brings to new-money funds as Bidding Agent, and issuers that want an independent solicitation on their portfolio can have mGIC bid it through a no-obligation conversation.

mGIC's fee for that work is paid by the winning provider rather than the issuer, is at or below the safe-harbor maximum in the Treasury arbitrage regulations, and is disclosed.

mGIC sells no proprietary investment product and does not act as principal in the investments it evaluates; as an SEC-registered municipal advisor it owes its municipal clients a fiduciary duty.

Risks: reinvestment and mismatch

Two risks this structure carries are mismatch risk, where draws run ahead of or behind the maturities, and reinvestment risk, where maturing principal is put back to work at rates different from those at bidding.

When draws run faster than the ladder, securities are sold before maturity, and the price received is whatever the market pays that day, which can be below the purchase price.

When draws run slower, cash builds up short and each maturity reprices into the rate environment of its own date, not the one the portfolio was bid into.

GFOA's guidance runs the same direction: keep the investment duration no longer than the expected drawdown schedule and revisit the draw schedule periodically as actual spending becomes clear; the spend-down mismatch page covers the divergent case.

Slow spending has a cost even when nothing is sold, the negative arbitrage that GFOA's advice to stage bond issues over the construction period and not issue well before spending begins is meant to limit; the negative arbitrage page walks through it.

None of this reorders the priorities mGIC works to on a fund: safety first, then liquidity, then yield.

If a current fund's ladder and its actual draws have drifted apart, mGIC offers a free, no-obligation reinvestment review, and its daily rate-update emails carry Treasury yields, SOFR and SLGS links each business day.

Final determinations about an issue's arbitrage status, permitted investments and required documentation belong to bond counsel and tax counsel.

Last updated 2026-10-06.

This page is general educational information about municipal finance and federal and state rules as of the date shown. It is not legal, tax or investment advice, and it is not a recommendation about any particular investment. Product availability, legality and suitability depend on the issuer, jurisdiction, governing documents and transaction-specific facts. Final legal and tax determinations remain with the issuer's bond counsel, tax counsel and other advisors.