The Nihon Keizai Shimbun Inc. said Wednesday that a special quotation fixation day was a major factor behind the heavy trading of specific issues during the two days before the announcement of a change in the benchmark Nikkei stock average's components in April, denying a report linking the deals to possible insider trading.

Nihon Keizai was responding to a Monday report by Kyodo News that said the Securities and Exchange Surveillance Commission has asked securities houses to submit reports over possible insider trading as almost all of the 30 shares dropped from the index experienced dramatic rises in trading shortly before the announcement of the change in the index.

Nihon Keizai announced the reshuffle on April 15. It took place on April 24.