Maiman founded the Merhav Group in 1975. He serves its president and chief executive officer. Through a subsidiary, it invests in sugarcane and ethanol production, It also owns a concession from the Egyptian government to export natural gas to Israel. Additionally, it "modernized a refinery in Turkmenistan" and a "water treatment and sewage systems in Venezuela". Maiman acquired the Ampal-American Israel Corporation from Beny Steinmetz for US$174 million in 2002. He served as its chairman from 2002 to 2013, and as its president and chief executive officer from 2006 to 2013. According to Globes, Maiman stepped down as a result of losses incurred in the wake of the Egyptian revolution of 2011, when contracts for the distribution of gas between Egypt and Israel fell through. Maiman invested in Channel 10, an Israeli television channel, in 2003, becoming the largest shareholder alongside Arnon Milchan, Ron Lauder and Rupert Murdoch. However, he divested from the channel in 2009. Additionally, Maiman served as the chairman of Eltek, a manufacturer of printed circuit boards, and Gadot. He is a shareholder of the East Mediterranean Gas Company. Maiman is the owner of Ecoteva Consulting, a real estate development and rental company in Peru. The company was founded in 2009 or 2011. After former president Alejandro Toledo was indicted on allegations of corruption over the purchase of property via the company in 2013, whereby he might have taken bribes from the Brazilian companies Camargo Corrêa and Odebrecht for the construction of the Interoceanic Highway, the company was accused of money laundering via an offshore company based in Costa Rica; the Swiss Financial Market Supervisory Authority said the money went from Confiado International Corp, a Panama-based company, to Costa Rica. By 2015, Maiman responded by saying he was the victim of a smear campaign. The two men, alongside Tolerado's wife, Eliane Karp, and three others, were summoned to court in 2016. During the trial, the prosecutor, Marco Cárdenas, suggested Maiman's financial privacy should be lifted to complete his investigation. Maiman served as the honorary consul of Israel to Peru and the Special Ambassador of Israel to Turkmenistan. He serves on the board of governors of Tel Aviv University.
Personal life
Maiman is married, and he has three children. He resides in Herzliya, Israel, where he owns two properties, one of which is in Herzliya Pituah. He also owns apartments in Miami and New York in the United States, and two yachts, one of which he sold in 2012.