Head of corporate PR Laity had led the web giant's in-house press office until his recent surprise departure.
It is the latest in a number of job cuts at the search engine. Last month, Yahoo let 1,000 employees go, with a spokesperson calling the redundancies 'targeted reductions' and blaming the cuts on 'aligning resources'.
Acting director of comms Rose Davidson remains at the web outfit, with global agency Hill & Knowlton providing PR support.
Davidson was appointed as an interim measure. European corporate comms director David Sawday left for AIM-listed tech start-up Phorm in January. Sawday had been at Yahoo since 2005.
Yahoo has faced mounting scrutiny after its rejection of Microsoft's £22.4bn takeover bid. While still one of the internet's best-known brands, the company has struggled against competition from Google. Its problems have been compounded by upheaval in its UK offices, with top sales staff defecting to rival Facebook.
The company is reportedly scrambling to delay a proxy fight with Microsoft, weighing up offers from News Corp and Time Warner, among others, that would allow it to remain independent.
Microsoft CEO Steve Ballmer last week announced that his company still intended to buy Yahoo to take advantage of the lucrative internet ad market.