Since 2014, Siman serves as President of EM.Co which oversees the operations for Tim McGraw. Major successes include a performance by McGraw on the 2015 Oscars; a Clio Award for an integrated campaign for "Humble and Kind" helping propel the song to such honors as a Grammy for Best Country Song, CMA Song of the Year, NSAI Song of the Year and Favorite Country Song AMA's. Billboard Magazine named Siman one of their 2018 Power Players for his work with McGraw and helping oversee the launch of his Soul2Soul World Tour with Faith Hill, garnering them the Legends of Live award and Billboard's No. 1 country music tour for 2017. He was named to the Billboard list again in 2019. McGraw headlined the VIP Tailgate Pregame at Super Bowl 53 in 2019, and released two books which reached #2 on the New York Times Bestseller lists. McGraw headlined the College Football Championship game in his home state of Louisiana in 2020. EMCo helped oversee the launch of McGraw's fitness brand, TRUMAV, with the establishment of the first fitness center in Nashville, Tennessee. Nielson Broadcast Data System named Tim McGraw the artist with the biggest radio audience for all genres, all artists, for the 2010s.