PerimeterX Inc., a cybersecurity provider backed by $77 million in funding, has dipped into its venture capital war chest to acquire fellow startup PageSeal Ltd.

The company announced the deal today without disclosing financial details. PerimeterX, which sells tools for securing websites and mobile apps, is relaunching PageSeal’s software as a cloud service called PerimeterX Page Defender.

Page Defender enables companies to provide a layer of defense for site visitors whose computers are infected with malicious browser extensions or adware. Such malware is often designed to hijack browsing sessions, for example by overlaying popups on legitimate web content. Page Defender uses machine learning to neutralize malicious elements that external scripts attempt to inject into browsing sessions.

PageSeal raised $1 million in funding prior to the acquisition. In a blog post, PageSeal chief executive officer Ken Zwiebel wrote that the startup’s software had been adopted by several “well-known brands,” but indicated his team decided to join PerimeterX because the product didn’t attract customers fast enough.

“As we launched the PageSeal product in early 2018, it became very evident that our first challenge would be market education,” Zwiebel wrote. “Market education takes a long time and costs a lot – both tough things for a seed-level startup.”

“We specifically chose to join forces with PerimeterX – seeing the obvious ability to scale quickly and bring our product to a large customer base from our first day as part of PerimeterX,” he added.

Zwiebel is joining PerimeterX in the role of general manager along with the rest of the PageSeal team. The startup lists 7 employees in total on LinkedIn. The new PageSeal-based Page Defender service, in turn, will complement PerimeterX’s existing web security tools, which block bot traffic and help companies identify when the external components they use in their sites display unwanted behavior. 

Photo of PerimeterX founders: PerimeterX