Per IRS Publication 1346 Electronic Return File Specifications for Individual Income Tax Returns, Part 1, page 335, the first two digits of a valid Employer Identification Number (EIN) must match one of the EIN prefixes listed below:

EIN Prefixes

01, 02, 03, 04, 05, 06;
10, 11, 12;
13, 14, 15, 16;
20, 21, 22, 23, 24, 25, 26, 27;
30, 31, 32;
33, 34, 35, 36, 37, 38, 39;
40, 41, 42, 43, 44, 45, 46, 47, 48;
50, 51, 52, 53, 54, 55, 56, 57, 58, 59;
60, 61, 62, 63, 64, 65, 66, 67, 68, 69;
70, 71, 72, 73, 74, 75, 76, 77;
80, 81, 82, 83, 84, 85, 86, 87, 88;
90, 91, 92, 93, 94, 95, 96, 97, 98, 99.