The letter isn't that long, and I find the press release less useful than the full text. It's also signed by many more publishers than just the ACM.

> Dear President Trump:

> The undersigned organizations represent the leading publishers and non-profit scientific societies in the United States. We write to you with deep concern regarding a proposed policy that has come to our attention that would jeopardize the intellectual property of American organizations
engaged in the creation of high-quality peer-reviewed journals and research articles and would
potentially delay the publication of new research results. The role of the publisher is to advance
scholarship and innovation, fostering the American leadership in science that drives our
economy and global competitiveness. As copyrighted works, peer-reviewed journal articles are
licensed to users in hundreds of foreign countries, supporting billions of dollars in U.S. exports
and an extensive network of American businesses and jobs. In producing and disseminating these
articles, we make ongoing competitive investments to support the scientific and technical
communities that we serve.

> As noted above, we have learned that the Administration may be preparing to step into the
private marketplace and force the immediate free distribution of journal articles financed and
published by organizations in the private sector, including many non-profits. This would
effectively nationalize the valuable American intellectual property that we produce and force us
to give it away to the rest of the world for free. This risks reducing exports and negating many of
the intellectual property protections the Administration has negotiated with our trading partners.

> We write to express our strong opposition to this proposal, but in doing so we want to underscore
that publishers make no claims to research data resulting from federal funding.

> To be clear, publishers both support and enable “open access” business models and “open data”
as important options within a larger framework that assumes critical publisher investments
remain viable. Under a legacy regulation that is still in force today, proprietary journal articles
that report on federally funded research must be made available for free within 12 months of
publication. This mandate already amounts to a significant government intervention in the
private market. Going below the current 12 month “embargo” would make it very difficult for
most American publishers to invest in publishing these articles. As a consequence, it would place
increased financial responsibility on the government through diverted federal research grant
funds or additional monies to underwrite the important value added by publishing.

> In the coming years, this cost shift would place billions of dollars of new and additional burden
on taxpayers. In the process, such a policy would undermine American jobs, exports, innovation,
and intellectual property. It could also result in some scientific societies being forced to close
their doors or to no longer be able to support the publication of U.S.-sponsored science that is
key to ensuring that the U.S. remains the world leader in science and technology.

> In addition to financing and managing a world-leading peer review process, publishers make
extensive investments in education, research, and innovative digital platforms that advance
American competitiveness and help ensure the quality and integrity of American science.
Undermining the marketplace is unnecessary, counterproductive, and would significantly harm
the system of peer-reviewed scholarly communication that fuels America’s leadership in
research and innovation.

> We urge you to oppose this proposed policy, and we look forward to working with the
Administration on this matter.