The Document Foundation blamed Microsoft for lock-in. HN blamed the author instead.

How Microsoft's "open" XML format stayed effectively closed

Italo Vignoli, a spokesperson for The Document Foundation, the nonprofit behind LibreOffice, argues that Microsoft's real lock-in mechanism isn't the operating system or the office suite. It's the file format underneath both. His account of how that happened starts with Office 2007, when Microsoft swapped its old binary DOC and XLS formats for XML-based DOCX, XLSX and PPTX, then pushed the new format through ISO standardization in what Vignoli calls "one of the most contested processes in the history of ISO," complete with procedural irregularities and contested votes.

The resulting OOXML specification runs to thousands of pages and, in his telling, mostly documents Microsoft's own existing software behavior rather than defining something other vendors can implement cleanly. There are two flavors: OOXML Strict, a cleaner version meant for genuine interoperability, and OOXML Transitional, which preserves Microsoft's legacy quirks. Transitional became the default and the one "only Microsoft's own software implements correctly," while Strict has quietly disappeared from recent Office releases. Vignoli's warning is institutional as much as technical: governments that archive official records in a proprietary format are handing custody of their own institutional memory to a single company. His fixes are concrete: adopt ODF, the ISO-standard alternative; move permanent archives to PDF/A; and treat open document formats as a governance requirement, not a nice-to-have.

The thread's sharpest shot landed on the essay's own author

The most-discussed reply in the thread wasn't about Microsoft at all. It dug up an old HN comment about Vignoli himself and used it to reframe the whole essay:

"I'm confident the person who most wants to sabotage LibreOffice's success is Italo Vignoli. Most of his blogs are about how awful OOXML formats are... This is a self-sabotaging marketing approach." — quoting a four-month-old HN comment, resurfaced by a reader who noticed the byline

The argument: complaining about Microsoft's formats for years, instead of closing LibreOffice's own feature gaps, functions as free anti-marketing for the product it's meant to defend. A second, longer reply took the opposite side entirely:

"Proprietary file formats are an industry standard. It is the lowest resistance way to deliver features... LibreOffice has to provide feature parity before complaining here." — in the thread

That framing didn't survive unchallenged. One reader described his own company's experience after ditching Microsoft on purpose:

"The one real problem we run into is PowerPoint decks that look different or get corrupted when used across different Office suites, including ones that are focused on Microsoft compatibility. Proprietary formats are a clear lock-in tool, because the cost of dealing with incompatibility is higher than the cost of paying the piper." — a reader whose company switched its whole office suite away from Microsoft

One reply came from an unexpected angle:

"LibreOffice was a big part of the problem. Their import code was half-baked, and silently changing Arial to Liberation Sans wasn't particularly liberating, either." — a reader who'd asked GPT to reverse-engineer old CorelDraw files from scratch

One more data point entered the thread as a plain citation rather than an opinion: Microsoft settled federal corruption charges over a bribery scheme in Hungary for more than $25 million, a fact one commenter dropped in as evidence that market share isn't always won on format merit alone. It doesn't prove Vignoli's argument, but it doesn't help his critics much either, government procurement being a messier thing than either "best format wins" or "best marketing wins."