After doing more research on TXP's situation I need to correct my previous post to you. I applied NASDAQ rules to TXP instead of the OTCBB rules when I mentioned SEC Forms 25 and 15 pertaining to voluntary withdrawl of a listed security. It seems TXP,as well as all OTCBB companies, cannot voluntarily withdraw from this exchange. They have to be removed for failure to file the required regulatory documents or when the last registered Market Maket withdraws from the stock.
The following is from OTCBB FAQ:
When can a company be "delisted" or removed from the OTCBB? OTCBB issuers that become delinquent in their required regulatory filings will have their securities removed from the OTC Bulletin Board. Further, all OTCBB issues must maintain at least one registered Market Maker to remain on the OTCBB. When the last Market Maker in a security withdraws from the stock, the issue is removed from the OTCBB after 4 days pursuant to Rule 15c2-11. An issuer cannot voluntarily withdraw from the OTCBB; only a market maker can voluntarily withdraw its quote from the OTCBB. If an OTCBB security becomes listed on NASDAQ or another exchange, it will no longer be eligible and will be removed from the OTCBB.