are they soaked on the outside but dry on the inside or completely soaked all the way through?
10k waterproof is the rating for the waterproof/breathable membrane that is bonded to the back of the fabric. if the pants are soaked on the outside but stay dry on the inside, the membrane is working just fine. outerwear fabrics typically have a water repellent treatment such as DWR(durable water repellent) finish on the outside which makes the water bead off. that is just a coating, not actual waterproofing. soaking through on just the outside would mean that the water repellent finish has worn off.
have you washed your pants recently? if they have a DWR finish, throwing them in the washer then dryer helps reactivate it. if that doesn't work, the nixwax or waterproofing sprays other people mentioned could be worth a shot.