Who stands behind a painting's authenticity? Auction house, marketplace, gallery or the artist
The party that signs or warrants the claim stands behind it. An auction house gives a written warranty with limits and a time window. A marketplace gives its own terms, and sometimes an artist-signed certificate. When you buy directly from the artist, the artist signs the certificate herself.
Authenticity is a statement, and someone has to sign it
A painting does not carry its own guarantee. What a buyer actually holds is a statement about the work (who made it, when, in what medium), made by a named party who accepts consequences if it is wrong. The useful question is therefore not "is this channel trustworthy?" but "who is making the statement, in what document, and what happens if it proves false?"
Amber Strata is a working example of the facts such a statement should fix. It is mixed media with acrylic on canvas, 150 x 100 cm, dated 2026, in the Terra & Ether series, priced at R$ 6,700 on its work page. Each of those lines can be checked against one record, and in a direct sale it is the artist's own record. The three channels below differ in who holds the pen.
At an auction house: a written warranty, with limits
Auction houses put the promise in their conditions of sale. Christie's Hong Kong Conditions of Sale (version of 7 May 2024) state that the house warrants lots as authentic, honours a claim notified within 5 years of the date of the auction, and offers one remedy: cancelling the sale and refunding the purchase price. The warranty applies only to the information in the first line of the catalogue description (the heading), does not apply to a heading qualified by terms such as "attributed to", and is available only to the original buyer. The house may require two expert opinions and the return of the lot at the buyer's expense (Christie's, accessed 1 November 2026). Other Christie's sale locations may publish their own conditions, so the sale's own document is the one to read.
The same logic appears at Sotheby's in its Buy Now Marketplace terms (last updated 9 March 2023, accessed 1 November 2026). The Authenticity Guarantee runs five years from the original purchaser's purchase. A "counterfeit" is defined as an item that in Sotheby's reasonable opinion is an imitation created to deceive as to authorship, and the remedy is rescission and refund. The buyer must give written notice within three months of receiving information that makes them question authenticity, and the guarantee cannot be transferred. These terms belong to Sotheby's marketplace product; the conditions for a live auction are a separate document.
The shared pattern: the house stands behind the catalogued attribution, for a fixed period, to the original buyer, with refund as the remedy. That is a real protection, and it is also narrower than the phrase "guaranteed authentic" suggests.
On a marketplace: read whose certificate it is
A marketplace sits between buyer and artist, so the first thing to read is which party issues the paper. Singulart's FAQ says that every artwork sold there comes with a certificate of authenticity signed by the artist, and that the platform selects its artists and may remove a work if its authenticity is questioned (Singulart FAQ, accessed 1 November 2026). In that model the artist's signature is on the certificate, and the platform's role is selection and moderation.
Marketplaces differ from one another, and terms change. Before buying, ask three things in writing: who signs the certificate, whether the platform's own terms add a remedy if the attribution is wrong, and for how long. For how listings are vetted and what buyer protection covers, see how online art marketplaces work.
At a gallery, and directly from the artist
A gallery sells on its own name and relationship with the artist, so the document to ask for is the gallery's invoice together with a certificate or letter, and the question is whether the artist or the gallery signs it. This guide does not rate galleries; the comparison between a gallery and a studio sale is set out in gallery or the artist's studio: what actually changes.
In a direct sale there is no intermediary to hold the claim. Every acquisition at Perfeito Studio is direct from the artist and includes the original, unique painting; a signed Certificate of Authenticity carrying the full technical record and the internal Archive ID; a fiscal invoice or official receipt; an Artwork Acquisition Agreement covering transfer of ownership, copyright and image use; an artist dossier; conservation guidance; and professional packaging. The certificate is signed by the artist and carries a QR code linking to the work's official page, so the record can be consulted at any time.
What the certificate does and does not prove is a separate matter; the legal weight of a certificate depends on where the sale takes place.
For whoever is about to acquire: what to ask for, in any channel
Ask for the statement in writing. The work's title, dimensions, year and medium, the signer's name, and an identifier that ties the paper to the object (an Archive ID, for instance). Compare it with the work page. Golden Passage, for example, is listed as mixed media, texture paste and imitation gold leaf (metallic leaf) on canvas, 60 x 80 cm, 2025, R$ 3,500; a document that described it as gold leaf without that qualification would not match the record.
Ask who is liable and for how long. At the auction houses above the answer is a refund within five years, to the original buyer. For any other seller, ask what they will do if the attribution is disputed, and keep the answer in writing.
Ask for evidence of the object. For buyers outside Brasília, detailed photographs and video of a specific work are available on request, and the work can be seen in person in Brasília by appointment (see shipping and international delivery for how the studio ships). Scale matters too: a 150 x 100 cm work such as Amber Strata is read against a sofa, and a 100 x 100 cm square such as Prism Garden against a smaller wall, so confirm the wall before the paperwork.
From the studio
From the studio: the record starts with the object
Alyne Perfeito is a Brazilian visual artist and trained architect based in Brasília. Her current body of work, painted between 2025 and 2026, is the studio's first documented one: every painting is unique, signed, catalogued under an internal Archive ID and photographed in detail before it leaves the studio. That order matters for authenticity, because the record is built from the painting itself. Amber Strata is worked in horizontal passages of ochre, bone and oxidized umber; Prism Garden in diluted washes left to run and settle; Golden Passage in sculpted texture paste with imitation gold leaf, which is sealed with a spray sealant. Those are the features a certificate's technical record describes, and a buyer can hold them against the work. A reader trained in architecture looks first at the wall and the scale; the paper comes after the wall is confirmed.
Frequently asked
Who guarantees authenticity when buying at auction?
The auction house, through the warranty in its conditions of sale. Christie's Hong Kong conditions of 7 May 2024 honour claims notified within 5 years of the auction, apply only to the catalogue heading, exclude qualified headings such as attributed to, and refund the purchase price to the original buyer. Other sale locations and houses publish their own terms, so read the document for the specific sale.
Does a marketplace verify the artist?
It depends on the platform. Singulart states that it selects its artists, that works come with a certificate signed by the artist, and that it may remove a work if authenticity is questioned. That describes selection and moderation, not an independent test of each painting. Ask the platform who signs the certificate and what its own terms add if the attribution proves wrong.
What does buying direct from the artist change?
The artist is the seller, so there is no intermediary between you and the person who made the work. At Perfeito Studio every acquisition is direct from the artist and includes a signed Certificate of Authenticity with the technical record and Archive ID, an invoice or receipt, an acquisition agreement and an artist dossier. The certificate carries a QR code to the work's official page.
Is an auction house guarantee permanent?
No. At Christie's Hong Kong, claims must be notified within 5 years of the auction, and the benefit belongs to the original buyer. Sotheby's Buy Now Marketplace terms also set five years from the original purchase and add a three-month notice rule. After the period the buyer has to rely on other legal rights, which vary by country.
Does a signed certificate prove a painting is authentic?
A certificate is the signer's statement about the work, backed by whatever record is attached to it. It is strongest when the signer is the artist, the facts match the object, and an identifier ties the two together. What it proves in law depends on the jurisdiction, which is covered in the guide on the legal weight of a certificate of authenticity.
Which channel is safest for a first purchase?
No channel is safe by name alone. Compare the documents: who signs the statement, what it contains, who is liable and for how long. Seeing detailed photographs, and the work in person where possible, adds evidence about the object that no certificate replaces. Ask every seller to put those answers in writing before you commit.
Ask the studio about a work
Write to the studio for the technical record, detailed photographs or video of a specific work.
Sources
- Christie's (Conditions of Sale, Hong Kong, 7 May 2024) — 2026-11-01
- Sotheby's (Buy Now Marketplace Conditions of Business for Buyers, last updated 9 March 2023) — 2026-11-01
- Singulart — 2026-11-01
- Perfeito Studio — 2026-11-01
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