The next requirement for an Individual Validated Code Signing Certificate is far less rigorous than the Identity Authentication requirement; you simply have to prove you have an active, listed telephone number.
And it's worth noting, Symantec and Thawte don't even take this step—they will call you on whatever number you give them during enrollment. Comodo is the only CA that requires Telephone Verification.
What is Telephone Verification
To satisfy the Telephone Verification requirement you must have an active telephone number listed that's verifiable by an acceptable telephone directory. That listing must contain your full name, physical address and of course a telephone number.
Currently, Comodo only accepts third-party telephone listings from Dun and Bradstreet or the Better Business Bureau (US businesses only).
Alternatively, if there is not a listing for you in an accepted third-party directory, Comodo can also use a Legal Opinion Letter. A legal opinion letter, sometimes called a Professional Opinion Letter or POL, is a piece of documentation in which an attorney or accountant – in good standing – essentially vouches for your personal information by signing a letter.
Once you've completed the Identity Authentication and the Telephone Verification, there's just one requirement remaining: the Final Verification Call.