Hi. You'll find many yarns, even ones more expensive than Lion - the yarns you find in a real yarn store - will have knots in them. Up to three in a skein is 'an industry standard' they say. The less expensive acrylics sometimes don't have any. So it just depends. The knots happen when the yarn on the big spools break as they're being wound into skeins. I pull on the knot and if it gives a little I'll cut it out and reknot it because I know mine won't come undone. Most people do just cut them out and join the way they normally do at the end of a skein.
sue- knitting heretic