By Liz Hoffman 

Corporate spinoffs, often done at the behest of activist investors, are also creating new prey for them.

U.S. companies this year have announced a record 64 spinoffs, in which they push unwanted or unrelated businesses out of the corporate nest as stand-alone entities, according to researcher FactSet, whose data begins tracking in 1998.

Activist shareholders that typically press companies for financial or strategic changes have agitated for many of the split-ups, contending disparate business units can drag down profits. But in a twist, many companies created by spinoffs are finding other activists quickly swarming to their stock.

Of 39 spinoffs that have begun trading over the past two years, about half count an investor with a history of activism among their 10 largest stockholders, according to FactSet.

Take CDK Global Inc., a provider of software to car dealerships. It began life as a public company Oct. 1 after being spun off from payroll giant Automatic Data Processing Inc.

Within three weeks, half of CDK's shares had changed hands, with many snapped up by activist hedge fund Sachem Head Capital Management LP. On Oct. 27, Sachem Head disclosed a 9.8% stake, filing a so-called 13D form reserved for influence-seeking investors. Earlier this month, another hedge fund, Fir Tree Inc., reclassified its 8.8% stake from "passive" to "active" against CDK management and said it had met with executives about the company's performance.

All told, CDK--which has filed just one quarterly earnings report--is about 20% owned by hedge funds with a history of boardroom agitation, according to public filings.

Advisers say activists sometimes see newly minted companies as attractive or easy targets.

"Funds are finding there's a much greater opportunity to influence a company's strategy early on," said Darren Novak of Houlihan Lokey, which advises both activists and companies. "The cement's still wet."

At the same time, some companies are protecting their spun-off businesses, in which they often still hold minority stakes, with defenses to hostile overtures such as staggered director elections that could try activists' patience.

So far, though, activists interested in spinoffs seem undeterred, advisers say.

Many spinoff businesses weren't a priority of their old parent or of Wall Street, meaning they might be poorly understood or undervalued by the market, advisers say. New management teams also are often perceived as more open to influence. They tend to be first-time public-company executives, having earlier run the business as part of a larger organization.

Moreover, the fledgling companies' shares tend to change hands quickly as investors unload stock they automatically received as part of the spinoff but don't necessarily want. Heavy trading can let activist funds build positions without drawing management's attention or driving the stock price higher.

Sachem Head, run by Scott Ferguson, a protégé of activist investor William Ackman, used heavy trading in CDK's early going to build its position, according to people familiar with the matter.

"Those first few weeks are a great opportunity to buy up a block, especially if an investor thinks the company is undervalued to begin with," said Jeffrey Shapiro, a lawyer at Lowenstein Sandler PC who advises both activists and companies.

Activists may find their traditional playbook harder to ply at spinoffs. Urging a sale of the company can be complicated by tax laws, which generally require a "cooling off" period between a spinoff and a sale to take advantage of certain tax benefits. Plus, the usual metrics of underperformance--lagging peers, slowing growth, depressed valuations--don't exist yet at brand-new companies.

"It's tough to say, 'This company hasn't performed well,' when there's been no history of performance," said Daniel Ganitsky, a corporate lawyer at Proskauer Rose LLP who advises boards of directors.

And some companies are padding their spinoffs with tougher defenses.

Zoetis Inc., the animal-health company that was spun out of Pfizer Inc. last year and now counts Mr. Ackman's Pershing Square Capital Management LP among its largest shareholders, has a staggered board. And Zoetis shareholders aren't entitled to demand a special, off-cycle board election, meaning Mr. Ackman would need to win back-to-back proxy fights over the next 18 months to take control of the board.

When hotel owner Ashford Hospitality Trust Inc. spun off its property-management business earlier this month, it gave the newly minted Ashford Inc. a staggered board, meaning only one-third of its director seats open up each year. And shareholders can't oust directors except during scheduled meetings once a year.

Ashford also adopted a so-called poison pill that effectively prevents any investor from owning more than 10% of its shares, citing "high volume and volatility in the trading" of its shares in its first few days as a public company. The poison pill is set to expire in March.

Ashford Chief Financial Officer Deric Eubanks said in an interview that the pill is meant to protect the company in its infancy.

"We wanted to make sure someone didn't try to come in before the company even had a chance to get its legs under it," he said.

Ashford was concerned in particular about hedge fund HG Vora Capital Management LLC, which had built a roughly 5% position in its former parent, according to people familiar with the matter. That gave HG Vora, which has run activist campaigns in the past, a sizable stake in the new company.

HG Vora increased its stake in Ashford to about 8% as of Nov. 24, though its choice of regulatory filing suggests it doesn't intend to push for control of the company.

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