The SEC has announced that:
The Securities and Exchange Commission today charged an online brokerage and clearing agency specializing in options and futures as well as four officials at the firm and a customer involved in an abusive naked short selling scheme.
The SEC’s Division of Enforcement alleges that Chicago-based optionsXpress failed to satisfy its close-out obligations under Regulation SHO by repeatedly engaging in a series of sham “reset” transactions designed to give the illusion that the firm had purchased securities of like kind and quantity. The firm and customer Jonathan I. Feldman engaged in these sham reset transactions in a number of securities, resulting in continuous failures to deliver. Regulation SHO requires the delivery of equity securities to a registered clearing agency when delivery is due, generally three days after the trade date (T+3). If no delivery is made by that time, the firm must purchase or borrow the securities to close out the failure-to-deliver position by no later than the beginning of regular trading hours on the next day (T+4).
The SEC, of course, thinks all naked short sales are "abusive." Frankly, I think that's ridiculous.
Christopher Culp and JB Heaton explain that:
Naked short selling simply switches the identities of the party owed shares and the party currently owning shares. In permissible short selling, the party owed shares is the security lender (who used to own the shares before lending them for short selling), while the party owning the shares is the new buyer. In naked short selling, the party owed the shares is the new buyer, while the party owning the shares is (still) the current owner. The buyer in both cases is the same, so the price should not be different. The only difference is who acts as the effective lender of the security: in permissible short selling, the lender is the current owner; in naked short selling, the new owner acts as the effective lender. From a price perspective, it is difficult to see how that matters. ...
We have shown that, from an economic perspective, naked short selling is not fundamentally different from traditional short selling, is unlikely to have serious detri- mental effects on capital markets, and might even present some benefits on balance.
Go read the whole thing for a nuanced take on the problem.