The regulator did not provide further details in its statement, published on Thursday.
Earlier this month, Tomov Development revised its initial bid, which was suspended at the time by the FSC.
Tomov Development is offering to pay 8.40 levs ($4.74/4.29 euro) per share, which values Velina at some 12.85 million levs.
Velina shares last traded on the Bulgarian Stock Exchange at a price of 8.35 levs.
(1 euro = 1.95583 levs)