SEC Form 10-KSB405 is a form used before the year 2003 under the Securities and Exchange Commission. It is highly similar to SEC Form 10-K405 except that the SEC Form 10-KSB405 is intended for small businesses. And just like SEC Form 10-K405, the purpose of Form 10-KSB405 was to signify the failure of a company officer or director to file a Form 3 or Form 4 or Form 5 on time which means that the company was not able to disclose the insider trading activities within the mandated time frame.