[13] On 3 April[14] 2014 J2 Global announced that it acquired Business Critical Software (also known as iCritical), a UK-based email security and management company.

[18] The company operates two divisions; the "Business Cloud Services" division includes firms such as eFax, Onebox, eVoice, VIPRE, FuseMail, Campaigner, KeepItSafe, VaultLogix, Callstream, Yotta280, Mailout Interactive, GDV, BackUp Solutions, SugarSync, Nuvotera, UnityFax, Firstway Digital, Excel Micro, Web24 Group, MXSweep, City Numbers, IPVanish, Livedrive, Moz, MetroFax, FoneBox, TrustFax, RapidFax, Send2Fax, SFax, SRFax, and Fax.com.

The company's digital media division, Ziff Davis, includes brands such as Mashable, PCMag, IGN and Everyday Health.

MyFax is an Internet business communication tool launched by the Ottawa-based software company Protus IP Solutions in 2009.

[25] On December 6, 2010, MyFax announced that it had been acquired by J2 Global Communications, Inc., owners of eFax,[26] which subsequently imposed restrictive terms and conditions on the client's right to local number portability.

[34] J2 Global has filed patent litigation cases against several companies, including CallWave,[37] Comodo, EasyLink Services International Corporation,[38] OpenText, Packetel, Protus, Venali and Zayo Group.

Some of the companies filed counterclaims, some of which alleged antitrust violations of Section 2 of the Sherman Act and California's Business and Professions Code §§ 16720 and 17200.