Most management has no idea of the importance of the open source building blocks that their business rests upon. Similarly they cannot begin to conceive of the benefits of making a donation. Probably the most effective thing you could do is to somehow attempt to copy the "greenwashing" effect of companies being environmentally responsible, and having an environmental section to their annual reports. "The health of the open source ecosystem is essential to sustainable research, development, and operations at ACME Corp. This year we have sponsored the following...for our current and future benefit".