Also, when a small company merges with a bigger business, it becomes less nimble because it is tied to legacy technologies of a larger corporation, and it can no longer innovate as quickly to keep up with competitors.

The history of the tech industry is littered with big deals that turned out poorly. In 2010, Hewlett-Packard bought Palm, the struggling mobile device maker, for $1.2 billion — and shuttered Palm’s operations after releasing the TouchPad, a tablet that was only on sale for about seven weeks before it was killed.

Similarly, Google bought the legacy handset maker Motorola Mobility for $12.5 billion in 2012 and, after sales of its first flagship smartphone were disappointing, reached a deal to sell it to Lenovo for $2.9 billion.

Image Adi Berenson, a PrimeSense employee, at the 2012 International Consumer Electronics Show. Credit... Julie Jacobson/Associated Press

“A lot of the tech acquisitions, in my opinion, have gone way off the tracks,” Mr. Thill said.

Apple has kept the stakes low in recent years. Several of the companies it has bought had as few as one or two people, like SnappyLabs, a one-man developer of a camera app. The founder, John Papandriopoulos, an electrical engineer, had developed an app to make the iPhone’s camera take high-resolution photos at a faster frame rate than Apple’s built-in camera software. Apple bought the company this year and made Mr. Papandriopoulos a software engineer.

These tiny acquisitions, made in large part to add the skills of an individual as much as the company, are known as acquihires in Silicon Valley. Most other major tech companies make them frequently as well. Facebook has been especially keen about buying small companies, like when it acquired Beluga, a group messaging app, to improve Facebook’s messaging services, and when it bought Push Pop Press, a digital book maker, to make its newsreader Paper.

When Apple buys a start-up with more than a couple of people, it is often looking for groups with specific skills who work well together as a team, according to a person who worked at a start-up Apple acquired last year, who spoke on the condition of anonymity because he was not authorized to speak to the press. Apple then takes these small teams and assigns them to new projects or pairs them with older teams at Apple.