There are 16 levels of license:

Single user (US$39.95) Purchase now
2 users (US$75)           Purchase now
5 users (US$160)         Purchase now
10 users (US$275)        Purchase now
25 users (US$475)        Purchase now
50 users (US$655)        Purchase now
100 users (US$895)      Purchase now
150 users (US$1195)    Purchase now
200 users (US$1495)    Purchase now
250 users (US$1795)    Purchase now
300 users (US$2095)    Purchase now
400 users (US$2595)    Purchase now
500 users (US$2995)    Purchase now
750 users (US$3695)    Purchase now
1000 users (US$3995)  Purchase now
1001+ users Please email sales@yaosoft.com