The small to midsized business security lessons to be learned? The ones you probably already know. Among the investigators' findings:
Watch for wireless weakspots: Indications are that the company breach may have taken place via insecure wireless networks at T.J. MAXX retailers. Any entry into your network is enough to compromise everything.
Upgrade promptly and efficiently: TJX took two years to convert its systems from weak to strong encryption. That's far too long -- more than long enough for two years' or so worth of customer data to be grabbed, in fact.
Systems exist to be monitored: Better monitoring -- i.e., constant, thorough, aggressive -- would have alerted the company to the breach sooner.
Acquire only the information you need and get rid of it when you're done: MAXX was acquiring driver's license numbers when refunding non-receipted items. That's an unnecessary data-get -- and exposed another customer record to hacking. Take only the information a transaction requires, and retain it only as long as your business and appropriate compliance/regulatory rules require.
Industry standards exist for industry reasons: Incredibly, the company was processing millions of credit card transactions without adhering to Payment Card Industry (PCI) standards.
Every one of these lapses was easily remedied, but more than that, every one of them was a breach of good business practice as well as good data security practice.
Take a look at your business with the lessons of T.J. LAX, uh, MAXX in mind.