IT businesses not only have a responsibility to their clients to follow the laws regarding sales tax on software but also to themselves. The executives running IT companies must keep the enterprises free of avoidable problems. Staying free of tax compliance controversies could prevent an IT company from dealing with time and cost-consuming audits.
Complying with tax codes in multiply states, however, could become a challenge. An IT company that sells software across state lines may need to pay tax on some or all sales. Ultimately, state law describes what is taxed and how much the tax is.
Not knowing the tax rules in a particular state won't make penalties automatically go away. The state tax authorities place the burden on the merchant to know such things. Unfortunately, it is not always easy for an IT company to figure out taxes.