It doesn't need the cash, but Verizon Communications recently issued almost $9 billion of new debt, and it's not alone. It looks as if companies are trying to lock in the current advantageous structure for making debt payments before a new, less-favorable tax proposal is adopted.

While President Donald Trump hasn't yet released the details of his "phenomenal" tax plan, analysts and investors widely expect that U.S. companies will no longer receive a tax benefit from interest payments paid on their debt. This belief is strong enough that it's helping to fuel a record pace of investment-grade bond sales this year.

The rush is being driven by a view among some on Wall Street that any debt in place before the reform passes will be deductible until it matures — a protective feature known as "grandfathering." Verizon appears to be setting itself up to make the most of this potential grace period.