ZeroSSL, xca - X Certificate and Key management, AboutSSL, CAcert, The SSL Store™, EJBCA, Smallstep Certificates, DigiCert, Dogtag Certificate System, SSL For Free, SSLTrust, OpenXPKI, Network Solutions, COMODO SSL, Pkcs11Admin, GeoTrust, ComodoSSLstore, Cheap SSL Shop, AppViewX CERT+, RapidSSLonline, WoSign, StartSSL, PKI.js, SSL2BUY, MEO File Encryption Software are some alternatives to Verisign.