Four tools still sell a licence that never expires

The picture

This entry surveys a living fact across four vendors' own current pages, not a dated event: as retrieved on 16 September 2026, Rhino, Houdini, SOLIDWORKS and TouchDesigner each still price a genuine one-time purchase option, against a market that has moved most comparable tools to subscription-only terms. Rhino's own sales page states that 'all purchased licenses are permanent and do not expire' and carries 'no maintenance fees,' priced from US$995 for a single seat. SideFX's buy page confirms Houdini offers 'perpetual or rental licences.' SOLIDWORKS's own how-to-buy page states customers may 'purchase yearly, quarterly, or perpetual SOLIDWORKS Design licenses.' Derivative's own licensing documentation prices TouchDesigner Commercial and Pro tiers at flat figures, $600 and $2,200, with no subscription or renewal term described on the page.

What the documents show

Three of the four vendors use the word 'perpetual' or 'permanent' themselves; Derivative's page does not use that word, and this entry treats TouchDesigner's status as inferred from the absence of any stated subscription or expiry term rather than as a vendor claim in those words. Each figure here is that vendor's own stated price and term, not a blended or averaged one, and none of the four pages describes a mandatory annual fee to keep the software running. No other tool in this site's manifest is described as offering a perpetual option unless its own vendor page states so; this entry does not extend that claim to any other tool.

What it is allowed to decide

A licensing term is not itself a decision-class authority over an image, but it bears directly on Auditability: whether a design file underlying a class-4 planning submission or a class-6 regulated artifact can be reopened years after a subscription would have lapsed. These four licences hold that authority in a way a subscription-only tool cannot guarantee once payments stop. None of the four vendor pages addresses Dimensional, Optical, Photometric or Physical authority, which depend on how the software is used, not on how it is purchased.

The disclosure label

A design history file produced in one of these four tools would carry a label reading: software licence type is perpetual per the vendor's own page as retrieved 16 September 2026; Auditability supported for future reopening independent of subscription status; other authorities not addressed by licensing terms; properly asserted by the studio's IT or licensing lead, not assumed from general market pricing trends.

• Is the specific licence purchased the perpetual option, or a rental or annual variant from the same vendor?
• Who in the organisation can confirm which licence type covers a given archived project file?
• Does the regulated deliverable's retention period exceed the vendor's own commitment to support the purchased version?

A perpetual licence purchased today says nothing about whether the file format itself will still open in ten years; that is a separate, unaddressed question.