ROME (Reuters) -Italian gaming group Lottomatica said on Thursday that majority shareholder Gamma Intermediate had completed the sale of a 6.4% stake, or 16 million shares, worth 152 million euros ($166 million). The sale was conducted through an accelerated book building process at 9.50 euros per share, at a 9% discount on the stock’s Wednesday closing price of 10.46 euros. The placement was aimed at institutional investors and there was no public offering. Gamma will retain a direct stake of 65.4% of Lottomatica’s share capital. Gamma has agreed to a 90-day lock-up for its remaining shares, …