> but the license file of tifflib states that you reserve the copyright.
Below is contents of TIFFLIB/LICENSE(LICENSE). Though I put "Acknowledgment:" at top of the document, I will not (should not) insist that I own the copyright of libtiff.
Quote:
0001.00 Acknowledgment:
0002.00
0003.00 Copyright (c) 1998-2004 Hideyuki Yahagi. All rights reserved.
0004.00
0005.00 THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
0006.00 EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
0007.00 WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
0008.00
0009.00 This software is subject to inherit original licenses.
0010.00
0011.00 - See LICENSE(COPYRIGHT) for TIFF Software copyright.
0012.00 - TIFF2PDF was distributed under GPL (GNU General Public License).
0013.00
0014.00 Note that this is only a 10-second-description which is not legally
0015.00 binding. Only the text in the LICENSE file is considered to
0016.00 completely describe the licensing conditions.
0017.00
0018.00 Contact author of original softeware for more information.
The libtiff Inherits original copyright and it also can be found at
"Acknowledgments and Other Issues" page.

Note that TIFF2PDF included in my distribution has different copyright (GPL). Newer libtiff has its own TIFF2PDF program but it is not the one I ported.
Hope this clarifies copyright issue.
uzaemon@Japan