With the moribund I.P.O. market, it's easy to see why underwriters like SPACs—they generate hefty fees. Perelman's MAFS, for instance, expects to pay its underwriter, Citigroup Global Markets Inc., nearly $40 million in fees. That sort of money has attracted other bulge-bracket banks like UBS, Lazard, Bank of America, and Deutsche Bank to this former backwater.

The founders of SPACs like the deals because, in a time of tight credit, they are able to take large and controlling positions in a cash-rich acquisition vehicle for a few cents on the dollar.

This has obvious allure to Perelman who used a supermarket chain to gobble up a cosmetics giant, bought out a comic book empire using the remnants of a video-rental company, and turned a maker of licorice extract into a collection of businesses encompassing check printing, test scanning, and data management.

If MAFS successfully completes an acquisition, its sponsor and management team—essentially Perelman and his closely held company MacAndrews & Forbes Holdings Inc.—will control 20 percent of the shares.

Still, just because such investing whales do well for themselves, does not mean that those who follow will reap the same rewards—just ask those who've stuck with Perelman-controlled Revlon, which has gone from an iconic American brand to a financial life support, struggling under its own debt and a stock price that can barely lift its head above one dollar.

SPACs also have a spotty history. In the 1980s, scam artists running blind pools, a SPAC forerunner, fleeced many investors. When SPACs started percolating in 2005, attorneys general in several states protested the American Stock Exchange's willingness to list them.

Backers countered that SPACs had been reformed. Most SPACs, for instance, held at least 80 percent of the proceeds from an offering in trust until an acquisition was made. The companies acquired generally had to have a market value of at least 80 percent of the SPACs assets, and most SPACs required 80 percent of shareholders to approve an acquisition for it to go through. If no acquisition target was found within a set period, typically two years, then investors were supposed to get their money back with interest, minus expenses.

John Nester, a spokesman for the Securities and Exchange Commission, says the S.E.C. currently has no concerns about the structure of SPACs, adding that most of them do "seek shareholder approval and offer shareholders the opportunity to get their money back instead of holding an interest in the combined entity."

But not all SPACs are created equal. The Financial Industry Regulatory Authority says it has open investigations in the area and that it is looking at how SPACs are both marketed and sold. State regulators have voiced concerns about price manipulation.

Meanwhile, several recent entrants have quietly chiseled away what were once standard protections outlined in their S.E.C. filings, protections at the very heart of SPACs current popularity boom.

Perelman-controlled MAFS has continued to reduce the level of shareholder voting rights with every subsequent filing of its proposed $500 million I.P.O. As of Feb. 12, the registration statement notes that an acquisition will go through if as few as 60 percent of MAFS stockholders agree.