Top Ships has put more than 50m shares up for sale to certain institutional investors, a week after buying three more tankers to add to its fleet of 12 ships.

The owner of "eco" vessels has priced 51.7m common shares at $0.135 each through a placement agency agreement with Maxim Group, according to a regulatory filing.

The shares offering, made following a shelf registration statement, is expected to close on or around 21 May.

A week earlier, the Nasdaq-listed owner bought three more tanker newbuildings from the private fleet of chief executive Evangelos Pistiolis.

Top Ships is paying just $18m to a company affiliated with its boss in return for three Marshall Islands companies that each own one scrubber-fitted 50,000-dwt MR vessel.

The ultra-high specification ships are being built at Hyundai Mipo Dockyard in South Korea for delivery in the first quarter of 2021.

Top Ships, which saw its shares decline 5% to $0.15 by mid-afternoon on Tuesday, already has four tankers built at the yard.

Pistiolis affiliate Central Shipping Monaco has three MRs listed as being built at the South Korean yard, due in January, February and March 2021.

It also has two suezmaxes due next year from Hyundai Samho Heavy Industries.

Last month, Top Ships and Swiss trader Gunvor each bought 50% shares in new 50,000-dwt MR tankers Eco Yosemite Park and Eco Joshua Park from Central Shipping Monaco for $27m.

Prior to the purchase, the two companies' joint venture sold the 49,703-dwt sisterships Holmby Hills and Palm Springs (both built 2018) in March and April.