600 Washington Blvd. in Stamford.

A large slice of Stamford’s 600 Washington Blvd. is going off the market with the relocation of an investment manager from Greenwich.

According to a report in the Stamford Advocate, Viking Global Investors plans to lease 42,000 square feet in the Rubeinstein Partners-owned building as it relocates its office from Greenwich.

The firm currently hangs its shingle at 55 Railroad Ave. in downtown Greenwich.

Fairfield County’s office market closed out 2022 with a vacancy rate just shy of  26 percent, Colliers reported earlier this month, as as leasing remained sluggish.

Greenwich’s office space has been the most resilient and most expensive in the area, with only a 15 percent vacancy rate and an average asking rent of $49.17 per square foot. Meanwhile, Stamford’s office market has the highest vacancy rate in the region of 32.1 percent and an average asking rent of $31.92 per square foot.