(Reuters) - Activist investor Starboard Value LP urged human resource services provider Insperity Inc (>> Insperity Inc) to explore a potential sale, calling the company deeply undervalued.

Starboard, which along with its affiliates holds about a 13.2 percent stake in Insperity, also suggested ways for management to improve execution, cut operating expenses and improve capital allocation.

Insperity can boost operating margins by cutting corporate overheads — including selling its two corporate jets — and shifting away from TV advertising and other sports-related marketing, Starboard said.

Starboard also suggested that Houston, Texas-based Insperity buy back shares.

Stadium Capital Management, which had about a 9 percent stake in Insperity in April, said last year that the company was "substantially undervalued".

Separately, Starboard also called for office-supply chains Staples Inc (>> Staples, Inc.) and Office Depot Inc (>> Office Depot Inc) to merge on Tuesday, saying a combined company would lead to greater savings.

Earlier this month, the investor also reiterated that Yahoo Inc (>> Yahoo! Inc.) should consider a merger with AOL Inc (>> AOL, Inc.).

Insperity, whose shares closed at $36.34 on the New York Stock Exchange on Tuesday, has a market cap of about $920.6 million, according to Thomson Reuters data.

(Reporting by Natalie Grover in Bengaluru; Editing by Simon Jennings)

Stocks treated in this article : Staples, Inc., Yahoo! Inc., AOL, Inc., Insperity Inc, Office Depot Inc