For those of you who file patents electronically or simply use the PTO's online forms in filing and prosecuting patents, you may have experienced some problems in the past with PDF forms that couldn't be saved. Many of these forms have now been improved, so recent versions may let you save information. But there are still some pitfalls. For example, the other day I was preparing an Information Disclosure Statement (IDS) for a client using the PDF form that pops up from the PTO forms page when you click on the link labeled "SB08a EFS-WEB," a form intended for online filing. Clicking on it opens the PDF file directly in your browser. TIP: save it as a PDF file and open it outside your browser with Adobe Acrobat. If you fill it out directly in the browser, I've found that the backspace key occasionally gets interpreted as a back-arrow click (in Firefox 3, anyway) that takes the browser to the previous URL, causing total loss of all the unsaved data in your PDF file. Aggravating.
Save, open with Acrobat, edit, and repeatedly save while editing with a simple Control-S.