American Tower is an American operator of wireless communication equipment. The company has more than 170,000 transmission systems for data transmission and communication, mostly masts, in 17 countries worldwide.
A Failure to deliver also known as fails-to-deliver or FTD occurs when a buyer or seller is unable to meet his trading obligations. FTDs for US listed companies are reported to the SEC and published twice a month. Therefore there is a certain delay between the reporting and the publishing of the data.
Number of shares, 3 months chart