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29 U.S. Code § 1414 - Asset transfer rules

(a) Applicability and scopeA transfer of assets from a multiemployer plan to another plan shall comply with asset-transfer rules which shall be adopted by the multiemployer plan and which—
do not unreasonably restrict the transfer of plan assets in connection with the transfer of plan liabilities, and
operate and are applied uniformly with respect to each proposed transfer, except that the rules may provide for reasonable variations taking into account the potential financial impact of a proposed transfer on the multiemployer plan.
Plan rules authorizing asset transfers consistent with the requirements of section 1412(c)(3) of this title shall be considered to satisfy the requirements of this subsection.
(b) Exemption of de minimis transfers

The corporation shall prescribe regulations which exempt de minimis transfers of assets from the requirements of this part.

(c) Written reciprocity agreements

This part shall not apply to transfers of assets pursuant to written reciprocity agreements, except to the extent provided in regulations prescribed by the corporation.