Intel Corp shares were all of a tiswas yesterday morning on rumours, later denied by IBM, that the latter had activated its rights under its cross-licence agreement with Intel and begun manufacturing the 80386 for itself: IBM said it had not yet started making the chip and wouldn’t speculate when it might; Intel shares had shed $1 at $30.50 by mid-morning New York time, when it was pointed out that even if IBM does make the chip, it is contracted to buy a substantial proportion of its requirement for 80386s from Intel through 1991.