A lot of CATxx cabling is not certified or tested to any particular spec by any entity other than the manufacturer themselves. They decide what to print on the cable sheath.

One can hope that the manufacturer of the cable you purchase or find already installed was scrupulous about actually meeting (or perhaps exceeding) the spirit and requirements of whatever claim/specification is printed on the outside.

Cable testing in-situ, with appropriate equipment, can provide some validation of actual cable performance.

I have a Pockethernet test unit, which can be useful at times. I have not used it a lot, but I do have it in my toolkit.