That first part is not as simple. Warner Media already had debt as a subsidiary which was transferred over in the spin-merge transaction (RMT). This qualifies as "proceeds" to AT&T since it gets rid of liabilities on the consolidated balance sheet. Additionally, in typical RMT's, for it to qualify as a tax-free transaction you need to have the shareholders that owned the entity that is spun-off (shareholders of AT&T in this case) own at least >50% of the newly combined company. So essentially WarnerMedia can only raise enough debt to reach that threshold.

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