Securities Lending

Securities lending is the transfer of a security from its holder to a borrower, secured by collateral, under an agreement to return identical securities. The SEC names the transaction in 17 CFR 240.10c-1a, titled "Securities lending transparency," which defines a "covered securities loan" as a "transaction in which any person on behalf of itself or one or more other persons, lends a reportable security to another person." FINRA's companion rule for broker-dealers is Rule 4314, "Securities Loans and Borrowings." The lender keeps the economic exposure to the security and gives up, for the term of the loan, the rights that attach to holding it. The borrower pays a fee for the use of the security and posts collateral against the risk of not returning it. Where the lender is an ordinary brokerage customer rather than an institution, the arrangement has its own rule book and its own disclosures, and that is fully paid securities lending.

Why a borrow market exists at all. Almost all of the demand traces to one rule. Under Regulation SHO, 17 CFR 242.203(b)(1), a broker or dealer "may not accept a short sale order in an equity security from another person, or effect a short sale in an equity security for its own account," unless it has borrowed the security, entered a bona-fide arrangement to borrow it, or has "reasonable grounds to believe that the security can be borrowed so that it can be delivered on the date delivery is due," and has documented that compliance. Short selling is where that obligation lands, and the four duties a short seller takes on sit with that term. The consequence for the lending side is simply that someone has to be willing to lend, and that willingness is priced.

Collateral is the whole of the lender's protection, and the rules are specific about it. Where the lender is a brokerage customer and the borrower is the customer's own broker, SEA Rule 15c3-3(b)(3) sets the terms. The written agreement must specify that the broker provides collateral "which fully secures the loan of securities, consisting exclusively of cash or United States Treasury bills and Treasury notes or an irrevocable letter of credit issued by a bank," or other collateral designated as permissible by order. The broker must "mark the loan to the market not less than daily," and where the market value of the loaned securities at the close of business exceeds 100 percent of the collateral held, must deliver more collateral by the close of the next business day so that the total is "not less than 100 percent of the market value of the securities loaned." Nothing in that arrangement is a guarantee of return; it is a promise to keep the security covered day by day.

The tax position is a deliberate exception, and it has a catch in the character of what arrives. Ordinarily, handing over a security in exchange for something else is a disposal. IRC 1058 carves out a qualifying loan: "no gain or loss shall be recognized on the exchange of such securities by the taxpayer for an obligation under such agreement," and 1058(c) gives the returned securities the same basis as the ones transferred. To qualify, the agreement must "provide for the return to the transferor of securities identical to the securities transferred," must "require that payments shall be made to the transferor of amounts equivalent to all interest, dividends, and other distributions which the owner of the securities is entitled to receive" over the term, and must "not reduce the risk of loss or opportunity for gain of the transferor." So a lender is not deprived of the cash a distribution would have paid. What changes is the label: the money arrives as a substitute payment rather than as the distribution itself, and IRS Publication 550 lists "[p]ayments in lieu of dividends, but only if you know or have reason to know the payments are not qualified dividends" among the distributions that are not qualified dividends. The rate structure that turns on that distinction sits with the qualified dividend.

The transparency regime exists on paper and is not operating. Rule 10c-1a, adopted in 2023, would require whoever agrees to a covered securities loan to report a list of data elements to a registered national securities association by the end of the day, including the loan's size, the collateral type, the rebate rate or lending fee, the collateral percentage and the termination date, and would require that association to publish most of them by the next morning, holding the loan size back for twenty business days. None of that is happening. In August 2025 the Fifth Circuit remanded the rule to the SEC without vacating it, in order for the agency to consider and quantify the rules' cumulative economic impact, and otherwise denied the petition for review. The SEC then issued an order in December 2025 in which it "grants the temporary exemptive relief, as set forth in this Order, from compliance with Rule 10c-1a regarding the reporting date until September 28, 2028, and from compliance with Rules 10c-1a(g) and (h)(3) regarding the dissemination date until March 29, 2029." A rule remanded without vacatur and then exempted is neither in force nor struck down, and it can be revived without new rulemaking. The practical point for a reader is that no lending rate or loan volume for an individual security is publicly available today, and none is due before 2029.

A borrower who needs a specific security approaches a lender or an intermediary. They agree a fee, expressed as an annualized rate on the market value of the loaned securities, and the borrower delivers collateral. The loan is marked to market for as long as it runs, with collateral moving in either direction to keep the coverage at or above the required level. The borrower passes through the equivalent of any distribution the security pays. When either side ends the loan, identical securities go back to the lender and the collateral goes back to the borrower.

A hypothetical, using round numbers rather than any real lending rate. Priya's brokerage borrows 10,000 shares she holds, trading at $40, so the loaned securities are worth $400,000 at the outset and the broker delivers $400,000 of cash collateral. Suppose the agreed fee rate is 2 percent a year and the loan runs 30 days. The gross fee is $400,000 x 0.02 x 30/365, which is $657.53. How that gross fee divides between the parties is set by the agreement and is not fixed by any rule. Now suppose the shares rise to $44 while the loan is open. The loaned securities are worth 10,000 x $44, or $440,000, against $400,000 of collateral, so the broker has to deliver at least another $40,000 by the close of the next business day to bring the collateral back to 100 percent. Priya's economic exposure to the shares never changed: she still gains the $40,000 of appreciation, because the loan moved the securities and not the risk.

Pros

• It produces revenue from a holding without selling it, which is why funds and custodians do it at scale.
• The loan itself is not a taxable event under IRC 1058, and the returned securities keep the original basis.
• The lender's economic exposure is unchanged by design, since 1058(b)(3) requires an agreement that does "not reduce the risk of loss or opportunity for gain of the transferor."
• Full collateralization, marked at least daily, is a rule rather than a courtesy where a broker borrows from its own customer.

Cons

• The lender's recourse if the securities are not returned is the collateral, not the securities, so a shortfall between the two is the exposure.
• Rights that attach to holding the security, voting among them, generally move with it for the term of the loan.
• What comes back in place of a distribution is a substitute payment, which can be taxed differently from the distribution it replaces.
• No public data on lending rates or loan volumes for an individual security exists, and the rule that would produce it is exempted from compliance until 2028 and from public dissemination until 2029.
• A loan can end on the lender's or the borrower's initiative, so neither side can count on a fixed term unless the agreement provides one.