The Double Irish’
On advice from Ernst & Young, Forest Laboratories Ireland reorganized that year, dropping the country from its name. The newly dubbed Forest Laboratories Holdings Ltd. established a registered office in Hamilton, Bermuda, declaring the island its tax residence. This unit took control of licensing the patents.
A second subsidiary in Ireland inherited the old name. It handled the manufacturing, sublicensing the rights to the patents, according to a corporate disclosure and an internal Forest flow chart tracing the arrangement that was reviewed by Bloomberg.
The change helped the Irish subsidiary cut its effective tax rate to 2.4 percent from 10.3 percent the year before the reorganization, according to its annual reports. It did so by deducting from its taxable income the fees that went to Bermuda, which has no corporate income tax. Charlie Perkins, a spokesman for Ernst & Young, one of the so-called Big Four, declined to comment on its work for Forest.