Ask the internet why your favourite fragrance changed and you get one answer: they cheapened it. Ask why oakmoss disappeared and you get another: it was banned.
The first is sometimes true. The second is false.
Who IFRA actually is
The International Fragrance Association was founded in 1973 and is based in Geneva. It sets standards for the safe use of fragrance materials, based on assessments carried out by the Research Institute for Fragrance Materials, which runs the toxicology, skin sensitisation, phototoxicity and environmental work.
IFRA is not a regulator. It has no legal authority and imposes no legal obligation. It is a voluntary, self-regulating industry system, and its standards bind members because members agree to be bound.
That cuts both ways, and you should hold both halves. An industry writing its own safety rules has an obvious conflict of interest. An industry that writes rules strict enough to destroy its own most famous fragrance family is not obviously acting in bad faith.
The standards are revised continually. The 51st Amendment, the most recent to be formally notified, brought the total to 263. The 52nd has not been notified as of late August 2026: its public consultation closed on 12 June 2026, and at the time IFRA said it expected formal notification toward the end of November 2026. It proposes 51 new restriction standards, 18 revisions, and a consolidated furocoumarin policy.
Which means the 263 figure above has a short shelf life. Take that as the working example of why every number here carries a date.
This is not a settled rulebook. It is a moving one, and that is why fragrances keep changing.
Oakmoss, done properly
Oakmoss is not banned. Two of the things in it are.
Oakmoss contains atranol and chloroatranol, which are potent contact allergens and were among the largest causes of fragrance contact allergy on record.
2008, IFRA's 43rd Amendment: capped atranol and chloroatranol at under 100 parts per million each in oakmoss and treemoss extracts, with a maximum of 0.1% of the extract in fine fragrance.
2017, the European Union: Regulation 2017/1410, in force 23 August 2017, prohibited atranol and chloroatranol outright, along with HICC, the material sold as Lyral. From August 2019 no new non-compliant products could enter the EU market, and from August 2021 existing ones had to be withdrawn.
So the material can still be used. What is sold now is oakmoss extract with those two constituents stripped out, and it does not smell the same, because the removed constituents were part of what gave oakmoss its smell.
That is why the chypres are not what they were: not cost-cutting, not a ban, but a targeted removal of two molecules that were putting people in dermatology clinics.
Mitsouko is the standard reference here: what is in a bottle today is a chypre rebuilt without those two molecules.
The other big lever: labelling
The EU's second tool is not restriction but disclosure, and it landed in 2026.
Regulation (EU) 2023/1545, adopted 26 July 2023 and in force from 16 August 2023, added 56 new fragrance allergens to the 24 the EU already required to be named individually on a label.
They must be declared when present above 0.001% in a leave-on product and 0.01% in a rinse-off product.
The deadline for new products placed on the market was 31 July 2026. Products already on the market have until 31 July 2028.
If you buy a fragrance in Europe now and the ingredient list looks suddenly enormous, nothing has changed in the bottle. The label got more truthful.
For a reader with sensitive skin this is one of the most useful regulatory developments in years, because for the first time you can look at a box and find out whether the thing that gives you a rash is in it.
Canada is doing the same thing
Everything above is European, which is how almost all fragrance regulation writing reads, and it has left Canadians with the impression that none of it applies here. That stopped being true in 2026.
For decades Canadian cosmetic labelling let a manufacturer write "parfum" or "fragrance" as a single ingredient and disclose nothing about what was inside it. Whatever the EU required, a bottle bought in Canada told you nothing.
Health Canada registered SOR/2024-63 on 12 April 2024 and published it in the Canada Gazette, Part II, and it brings Canadian labelling into line with the EU. Named fragrance allergens must appear in the ingredient list above 0.001% in a leave-on product and 0.01% in a rinse-off, the same thresholds the EU uses.
For products already on the market before 1 August 2026, it phases in over roughly four years: the original 24 allergens from 12 April 2026, two years after the regulation's own registration date, then the full expanded list by 1 August 2028, per Health Canada's own guidance. Any cosmetic newly placed on the Canadian market from 1 August 2026 onward has to carry the full list from day one. Those Canadian dates land in step with the EU's own cutover dates for the matching step, and that is not a coincidence: Health Canada's own regulatory analysis for the rule says it incorporates the EU list, including its transition period, by an ambulatory reference, which is a lawyer's way of saying the Canadian deadlines are pegged to the European ones on purpose.
Where the sources still disagree. The total number of allergens on the list is a real case of two primary sources disagreeing with each other. The European regulation's own text states the pre-existing count as 24 and the newly added count as 56, without ever stating a summed total. Add them and you get 80. Health Canada's own regulatory text for the Canadian rule states the number differently: 81 entries. We could not find a version of either regulation that resolves the one-entry gap, so we are printing both figures rather than picking one. What is not in dispute is the direction: the fragrance allergen disclosure list has more than tripled in size.
One further wrinkle matters here, because it shows how these things actually get made. On 6 March 2026 Health Canada relaxed part of its own rule: the original amendment required full concentration disclosure for fragrance allergens on the Cosmetic Notification Form, and that is now optional for most, with mandatory disclosure kept only for substances restricted under the Cosmetic Ingredient Hotlist.
So the label tells you more and the filing behind it tells the regulator less, in the same year. Regulation is a negotiation, not a decree.
What this means for you, practically. A fragrance released in Canada from mid-2026 onward carries an ingredient list that names the allergens in it. An older bottle on the same shelf does not, and will not until the phase-in above catches up to it. If you react to fragrance, the newest bottle in the shop is now the most informative one, which reverses the usual advice about buying older stock.
Somebody has to decide, and they have a name
Reformulation gets discussed as though it happens to a fragrance, passively, like weather. It does not. A person sits down and decides what a fragrance becomes when the thing it was built from is no longer available.
At Guerlain that person is Thierry Wasser, the house's fifth head perfumer and the first from outside the family, in post since 2008. Alongside his own work he reformulates the classics, including Shalimar and L'Heure Bleue.
So when you smell Mitsouko, Shalimar or L'Heure Bleue today, you are smelling Wasser's current version, built under constraints he did not choose: an oakmoss he cannot use as it was, materials that have become unobtainable, and a house that expects the fragrance to still be recognisably itself.
"They ruined it" assumes carelessness. What actually happened is that somebody skilled had to choose which of a fragrance's qualities to sacrifice, and our guide to the perfumers has his profile.
Why fragrances actually get reformulated
Regulation. IFRA restricts a material, or the EU bans one, and every formula containing it must be rebuilt. Oakmoss, Lyral, and the furocoumarin work in the 52nd Amendment are all of this kind.
Material availability. Our guide to fragrance materials has the examples. Mysore sandalwood collapsed to a small fraction of its former harvest. Vanilla has swung wildly in price after crop shocks. A formula built on a material that is no longer obtainable at any sane price has to change or stop existing.
Cost. This does happen. A brand under margin pressure instructs a lower raw materials cost and the formula gets rebuilt cheaper. This is the reformulation people are angry about and they are right to be.
Improvement or drift. Sometimes a house thinks it can do better. Sometimes a batch of a natural material simply differs from the last one, which is not reformulation at all but gets reported as it.
There is a fifth and nobody counts it. The brand changed hands. Our guide to who owns fragrance houses has the mechanics: most designer fragrance is made under licence, those licences move between a handful of large companies for serious money, and the new holder rebriefs the formula. Our guide to the fragrance industry right now covers what that churn looks like from the shop floor. When a fragrance you have worn for a decade changes and none of the four reasons above fits, check who owns it now.
The internet collapses all five into "they cheapened it." Two of them are outside the brand's control, one is arguably in your interest, and one is a contract expiring.
When it really matters and when it does not
It matters when the reformulated material was structural: oakmoss in a chypre, real Mysore sandalwood in something built around it, or the old hydroxycitronellal level in Diorissimo, now capped much lower than it once ran. In those cases you are smelling a different fragrance wearing the same name, and anyone who tells you otherwise has not compared them.
It matters less than the internet thinks in most other cases. Batch variation in naturals is normal and always has been. A nose that has been smelling a fragrance for fifteen years will register a change that a new buyer would never notice. And the vintage bottle someone is comparing against has itself been sitting in air and light for fifteen years, which changes a fragrance considerably.
"Vintage is always better" is not true. Older is not automatically better. Some vintage bottles have oxidised into something sour and dark. Some reformulations are better than the original, because the perfumer had better materials and a second attempt. What is true is that vintage is different, and if you love a specific version, buy that version and stop reading forums.
What to do about it
Date your bottles. Our guide to counterfeits and batch codes covers batch codes. If you love something, note what batch you loved.
Buy a backup of a fragrance you are attached to, especially if its house has just changed licensee, per our ownership guide.
Read the ingredient list now that it says something. From 2026, in Europe and increasingly in Canada, it does.
Do not chase vintage on principle. Chase it if you have smelled both and prefer the old one. That is a completely different decision.
Part of Nose to Bottle, our complete fragrance manual. Read it in order here.