How to Get Free NFTs That May Gain in Value

It’s June 2017. CryptoPunks — digital art pieces from what will become one of the most revered and valuable NFT collections that have just been launched and are being claimed for free by Ethereum users. 

Fast forward to 2022 and CryptoPunk #5822, a light blue alien punk with a bandana tied onto its head, is sold for $23.7M.

 It would be a dream come true for most people to ‌travel back in time to ’17 and claim one of those Punks for free. Claiming potentially valuable NFTs for free is a widespread online practice, but is it all it’s cracked up to be?

Can you actually get free NFTs that may gain value?

Let’s explore four good ways to get one online.

Get Free NFTs Via Play-To-Earn Games:

NFT gaming revolves around players earning NFTs that have actual value while having fun. Play-To-Earn (P2E) games help encourage people to buy and trade blockchain assets. Many P2E games run on the WAX blockchain and projects give users free NFTs to promote activity. 

If you’re not opposed to a bit of competition, you can earn free NFTs by playing games like Splinterlands and The Sandbox. These games allow players to win in-game items that can be sold for cryptocurrency by participating in daily quests or tournaments. 

Most NFT games have a booming marketplace where other players buy or trade in-game items. A game NFT may not be the next CryptoPunk, but it could grow to be of actual worth. 

There are several great NFT games to choose from, so it should be reasonably easy to find an NFT game that interests you. Besides free NFTs, NFT gamers can also earn cryptocurrency.

NFT Giveaways: 

Several NFT projects use giveaways to boost engagement or awareness for their project or express gratitude for their community’s support. These giveaways are most common on Twitter and Discord servers.

Following a project or an NFT influencer on Twitter is a good idea if you want to be aware of giveaways. You may be asked to retweet a post, share your ETH address, or follow specific accounts to win a giveaway. The winners are often chosen using a Twitter picker tool at random.

The downside to Twitter giveaways is that you may come across giveaway scams, where the Twitter user or project is using their giveaway post to gain followers without actually intending to gift an NFT. Do proper research on the user or project, so you don’t waste time and effort on these scam tweets. 

Another great way to get free NFTs is through giveaways in Discord communities. Projects trying to support their community may gift an NFT to a lucky member or have a process through which members can gain an NFT. To have access to these sorts of giveaways, you’ll have to be a member of the project’s Discord server. 

Just like on Twitter, some giveaways on Discord groups choose winners randomly. Projects may also make their Discord giveaways exclusive to members who already own their NFTs. 

NFT Airdrops 

Fractal, a popular NFT project based on Solana, recently airdropped 100,000 NFTs to members who registered. Several other projects are airdropping free NFTs, as airdrops are a common way projects raise awareness of their coin or NFT. 

All you have to do after finding an NFT airdrop is follow the process to register for the drop. Once it occurs, you’ll receive a token in your wallet. Enjin, a popular blockchain platform, sends free NFT airdrops randomly for users to claim. Free to Mint 

NFT projects also create free to mint tokens or free mints to boost interest in their projects. 

Free mints are NFTs you can claim without paying a minting fee to get the NFT. You’d still have to pay gas fees, which may be cheap or expensive depending on the project’s network. For example, Ethereum gas fees are costly compared to Near or Solana gas fees.

Security Tips

NFT airdrops, P2E games, giveaways, or free mints are all great ways to get a free NFT that may gain in value, but you should stay aware of possible scam projects or phishing attacks. 

Projects with free mints sometimes get hacked right before mint and there have been situations where user’s wallets were drained of funds after connecting their wallets to malicious links. If you’re interested in getting free NFTs, you should:

  • Always do your research. 
  • Avoid clicking on any link sent by a stranger to your DMs on Discord.
  • Do not rush to connect your wallets to mint an NFT until after a reasonable time. Some free mints last for hours or days, so you can usually wait to ensure  other collectors are claiming their free mints successfully. 
  • Keep in mind that no project admin would DM you to participate in a giveaway or free mint . 
  • Never give your seed phrase to anyone. 
  • Be part of an Alpha community. Alpha communities are the perfect place to get information on upcoming NFT Projects. 

Final Thoughts: Getting NFTs That May Gain In Value

Free NFTs are not hard to come by, but what sort of NFT you claim matters. If you want to get a free NFT that may gain exponentially in value, you  need to do your research.

You can learn about an NFT project from its whitepaper, Discord community and social posts. Most projects also publish updates on their timeline, growth or plans on a blog. It’s a good sign when a project offering giveaways or airdrops has:

  • A strong team. You should be able to find the person or people who are building the NFT project.
  • A clear vision or roadmap.
  • A growing community.

NFT Theft: 3 Times NFTs Were Stolen By Hackers

From single JPEGs worth $69M to the possibility of using NFT technology in real estate, it’s no surprise that these wildly useable tokens have attracted loads of attention, both good and bad. 

Losing an NFT is more than just losing a screenshot– it could be millions or multiple millions of losses. 

With a higher number of individual wallets suddenly becoming worth millions due to price increases, the rise of NFT theft is inevitable.

A quick refresher: as unique digital assets that live on a blockchain, NFTs represent anything from game assets or characters, songs, articles, digital art, and even tweets. The tokens themselves are valuable because they are unique and cannot be faked since they are blockchain assets– and markets respond accordingly to the provable scarcity. The actual trade value of an NFT depends on how well-known its creators are, its previous purchase value, ownership history. 

Now that we know what NFTs are and why they are valuable let’s talk about some times NFTs were stolen by hackers and how. 

OpenSea’s User Side Hacks 

OpenSea is one of the world’s largest NFT marketplaces. So when, in February 2022, several OpenSea users reported that their accounts had been compromised, it spread like wildfire. 

First, it was thought that the hack had led to NFT thefts worth about $200 million. 

Then, a Twitter thread posted by blockchain security analysis firm PeckShield was retweeted by the CEO of OpenSea. The thread shared a technical analysis of the hack, revealing that only about $1.7M worth of NFTs had been stolen, and that there were 17 users affected.

Whereas readers had initially believed that OpenSea itself was compromised, it came out that the hack occurred through a phishing attack. 

While it looks like only 17 users were affected by the attack, others are concerned that they may have been compromised as well, although these complaints have yet to be addressed by OpenSea. 

Even more, OpenSea faces legal action by one of the victims who lost a Bored Ape NFT worth millions. 

Besides the legal suit and the phishing attack, Fortune reports that OpenSea paid about $1.8 million to some of its users after a bug on its website allowed bad actors to purchase NFTs for less than what they were worth. 

The MetaMask Hack

Metamask is a secure wallet app and web browser known for storing Ethereum tokens and NFTs. 

In December 2021, a phishing attack impersonating Metamask Support invited users to seek help by filling out a Google Docs form. The form requested the user’s secret recovery phrase. A secret recovery phrase would allow a malicious actor to respawn a user’s wallet and steal its content. 

Seeing as Metamask is an ETH wallet, this would majorly affect a user’s NFTs.

Fortunately, the attack was discovered early and the phishing bot was flagged by Metamask.

Sleepminting: The Beeple NFT Theft

Beeple’s Everydays – The First 5000 Days is one of the most valuable NFTs in existence. Sold for a whopping $69M, this NFT rocked the blockchain universe.

So when it was hacked by someone called  “Mr. Nobody,” (aka Monsieur Personne), it was pretty alarming.

Sleepminting, first introduced by Personne, is a process that allows a hacker to “mint” an NFT under the name of someone without their knowledge or consent.

In April 2021, Personne, a self-acclaimed “white-hat” hacker, went on a mission to show the world how vulnerable the technology of NFTs are by attacking the most well-known NFT transaction. Personne sleepminted a second copy of Beeple’s Everydays – The First 5000 Days in Beeple’s name and then gifted the original, unapproved copy to someone named Arsene Lupin. 

Lupin listed the NFT on Rarible and OpenSea, starting at a 0.01WETH, a despicable price compared to its value. Rarible and OpenSea eventually canceled the listing. 

When contacted, Personne wrote, “The goal I want to achieve with this is to take the most expensive and historic NFT and show that if it is not protected, how can we guarantee that any NFT is safe from intentional malice, fraud, forgeries, theft, etc.?” 

Final Thoughts: NFT Theft 

NFTs have the potential to revolutionize hundreds of industries all over the world. As the technology advances, we’ll, unfortunately, most likely see some more thefts, and accompanying security improvements. 

As an NFT owner, keeping your assets secure is vital. 

  • Use secure wallets to protect your addresses from attack
  • Never give out your seed phrase
  • Only use complex passwords that include phrases, numbers, and symbols
  • Store all your passwords and phrases in physical form, locked away safely (not on your computer)

Don’t make it easy!

Top NFT-Based Trading Card Games (TCGs)

NFT-based games integrate traditional gaming concepts with blockchain technology, non-fungible tokens (NFTs), and other decentralized financial elements. 

Gamers are loving GameFi (the intersection of gaming and NFTs, and even DeFi) for three main reasons: 

  1. True ownership: While in conventional digital games, players can buy in-game assets, those assets don’t actually belong to them. On the other hand, NFT-based games give players complete control over their assets– in-game assets like cards, lands, avatars, or swords are NFTs.
  2. Verifiable rarity and uniqueness: Non-fungibility makes it possible for creators to make 100% unique tokens, as well as programming different rarity levels for the assets. Naturally, some items in games will be scarcer or more useful than others, and their value should reflect that. Since everything happens on the blockchain, it’s easy to verify the scarcity, uniqueness, and authenticity of each asset.
  • Opportunity to earn income while playing: These games implement play-to-earn mechanisms. By participating in games, players can earn cryptocurrencies and in-game items that have real-world value. Many games have their own secondary markets for trading.

NFT-Based trading card games are getting so much attention because they’re a perfect mesh for most any game genre, from role-playing games to fighting games. One of the most popular gaming categories is card trading. 

For many people, training card games, or TCGs, revive childhood memories of collectible card games while at the same time offering a new way of generating revenue.

In play-to-earn NFT-based card trading games, each card is a non-fungible token (NFT), usually in ERC-721 standards. They enable the play-to-earn mechanism using common elements found in GameFi, such as an in-game currency and a marketplace. 

Here are the top NFT-based trading card games. 

Gods Unchained

Gods Unchained is the most popular trading card game in the blockchain universe. It runs on Ethereum and Immutable X. 

Gods Unchained is a free-to-play fantasy-themed turn-based, tactical card game; players must build their decks based on a strategy. 

By playing the game, you can earn common core cards. Those cards can’t be traded on the marketplace; at this point, they are not minted on the blockchain. It’s possible to increase the value of these common cards, by earning “flux”, a resource gained by winning the ranked games.

Gods Unchained has a process called The Forge, in which players who have earned enough flux can merge two identical core cards into one by spending flux. This process creates higher-quality cards, and since the forged cards are minted on the blockchain, they can be sold on the blockchain, sometimes for a hefty profit. 

Splinterlands

Splinterlands game runs on the Hive blockchain. 

You can test the game for free, but to start playing, you need to buy a starter set for $10.You can get new cards by buying packs from the shop or individual items from other players in the marketplace. You can also sell your assets on this marketplace. 

One of the highlights of Splinterlands is its cross-compatibility with multiple blockchains, enabling users to trade their cards on several marketplaces. 

In addition to selling your cards, you can earn in Splinterlands by getting its in-game currency DEC (Dark Energy Crystals). There are a couple of ways to acquire DEC in the game. First, by winning ranked battles, and second by destroying the cards you don’t use anymore. You can use DEC to buy assets from the game’s shop.

Another way to earn on Splinterlands is renting your cards via peakmonsters.

Sorare

Sorare is a fantasy football game built on the Ethereum blockchain. 

You can collect player cards and build teams, and as with real-world trading card games, the real value comes from the most valuable player cards. Depending on the rarity of the card, it can get quite expensive.

The Sorare play-to-earn mechanism enables users to participate in tournaments, where users can earn points and rewards based on their team’s performance.

Dark Country Game

Dark Country is a trading card game on the WAX blockchain with gothic-themed characters like zombies, ghosts, and haunted Indians.

In addition to cards, players can own heroes, items, and lands as NFT assets. Players can stake Dark Country assets on rplanet.io and collect cards on collect.social to gain the platform’s Racoon tokens. 

Dark Country has a weekly forging activity similar to Gods Unchained’s The Forge called Heroes Reforge and Staking. Players need to burn four heroes of the same type in order to receive a new hero with better quality. They can then stake this improved asset to earn rewards.

Dark Country has recently introduced land assets compatible with WAX and Flow blockchains. 

With lands, several new revenue generation options will be possible soon, such as land leasing and staking the platform’s in-game currency Shadow Dime (SDM) on lands.

Final Thoughts: Emerging Exciting New TCG Projects

While some may argue that the game mechanics of most NFT-based games are primitive and “not quite there yet,” TCGs marry the simplicity of a trading card game with the blockchain very well. 

A few more exciting TCG projects to keep an eye on include:

  1. Skyweaver, a free-to-play Ethereum-based game in beta mode. Players have three grades of cards: base, silver, and gold. Base cards can’t be traded, but silver and gold cards can be. You earn silver cards via ranked rewards and conquest, and gold cards via conquest.
  2. Parallel,  a science-fiction-themed card game also based on the Ethereum blockchain. The team built its own NFT drop system. The project is currently raising funds by selling drops, which contain cards. These cards will have utilities once the game development is complete.
  3. Metropolis Origins, is a cyberpunk-themed card game by QXR Studios running on the WAX blockchain. It’s a sequel to game designer Graeme Devine’s adventure game Metropolis. The game released a founder NFT pack that enables owners to play the game in beta mode. 

The evolution of blockchain card games will be one to watch, as more implementations of conventional card games on the blockchain continue to emerge.  With NFTs’ programmable nature, we can expect to see the evolution of more dynamic, and potentially lucrative and competitive, playing card games in the near future. 

The Top Celebrity NFT Owners

With entrepreneurs, rappers, DJs, and professional sports players leading the way, more and more celebrities are joining in the NFT craze than ever.

Some launch their own NFT collections; some collect NFTs from other creators; some directly invest in NFT ventures. Some do all.

This guide will dive into the portfolios of the top celebrity NFT owners who have collected dazzling JPEGs from the most extravagant collections.

Let’s explore: which celebrity has the largest NFT portfolio so far? What projects are most popular? 

To explain, we compiled a celebrity NFT owner list based on DappRadar’s October and November reports.

Gary Vaynerchuk

Entrepreneur Gary Vee has been an NFT ambassador from its early days. Recently, he launched his own Veefriends NFT project that provides the owners three-year access to a multi-day conference called Veecon. Around 74% of his NFT wealth comes from his own collection. He kept 1016 Veefriends NFTs which have approximately $69M in market value.

He’s been collecting NFTs from other collections as well. As of writing, Gary Vee’s NFT portfolio is allegedly worth more than $90M. 

Some attention-grabbing pieces from his portfolio are:

  • 60 CryptoPunks. Cryptopunks is the revolutionary NFT collection launched in 2017 that started the crypto art movement. Cryptopunks collection represents one of the first examples of the non-fungibility concept on Ethereum. The most valuable editions in Vee’s collection are CryptoPunk #2424 and #2140.
  • 7 Bored Ape Yacht Club (BAYC). BAYC is a collection of 10,000 ape NFTs. It’s one of the most exclusive NFT collections. In recent months owning a BAYC NFT has become a status symbol in the crypto world. It serves as a digital identity that provides the owner access to exclusive membership club activities, like the collaborative graffiti board bathroom.
  • Three Meebits. It is another prominent collection by Larva Labs, the studio that made the legendary Cryptopunks.

Snoop Dogg

The famous rapper Snoop Dogg is one of the most influential NFT celebrities. He was an early promoter of Dogecoin; he partnered with the Sandbox Game on new land offerings; he collaborated with Chris Torres to launch the NyanDogg collection.

Last September, he revealed that he is actually the human behind the anonymous Cozomo de’ Medici, a popular NFT collector Twitter account that had launched in August. He said he wanted to separate his NFT business from other activities.

Here are some of the most valuable NFT assets he owns under the pseudonym Cozomo de’ Medici. The entire collection is valued at around $14M.

This is only Cozomo de’ Medici’s collection. We know that Snoop Dogg has also invested in BAYCs. He shared in a tweet that he acquired them through the NFT broker firm Moonpay.

Alexis Ohanian 

Another NFT frontrunner is Reddit co-founder Alexis Ohanian. His NFT collection includes 6 Cryptopunks, 2 BAYCs, 10 Meebits, and many others. The most valuable NFT in the portfolio is Cryptopunk #8115.

Ohanian gifted his wife Serena Williams a look-a-like punk (Cryptopunk #2950). He wore its image as a badge on his collar while visiting the 2021 MET Gala. 

All six punks in Ohanian’s portfolio are black female punks with headbands. The entire Cryptopunks collection has 3,840 female punks.

He also invested in the Cool Cats project with 7 NFTs. Cool Cats is a collection of randomly generated NFTs on the Ethereum blockchain. Owners are free to do anything with them under a non-exclusive license.

In addition, Ohanian minted 13 pairs of NFT sneakers and 4 Daypacks from the 10KFT collection. The 10KFT NFT collection allows NFT owners to create customized sneaker designs featuring their NFTs. But only a few exclusive NFT collections are accepted, such as BAYC, Cool Cats, and CrypToadz.

Steve Aoki

The most precious piece of DJ Steve Aoki’ NFT collection is BAYC #118, followed by Cryptopunk #8705. He has 794 NFTs in total. Other notable items from the collections are:

  • Swaggy Sea Lion from Gary Vee’s Veefriends collection.
  • Three M1 Mutant Serum NFTs, which had been airdropped to all BAYC owners. Its market value is around 9ETH.
  • Cool Cat #3350.
  • 5 CloneX NFTs. CloneX is an NFT collection co-created by the famous Japanese contemporary artist Takashi Murakami and RTFKT. RTFKT is a leading brand that delivers next-gen gaming sneakers and collectibles. It’s been acquired by Nike very recently.

Marshmello

Another celebrity who invested in Cryptopunks, BAYC, and Veefriends collections is DJ Marshmello. His portfolio has 120 NFTs with around $1M market value, including 11 NFTs from the Cryptoadz collection by Gremplin.

The most valuable three NFTs from his collection are:

  • Cryptopunk #8274
  • BAYC #4808
  • BAYC #9231

Post Malone

Among the top NFT celebrity owners, musician Post Malone might be the only one who doesn’t have any Cryptopunks. Instead, he has two BAYCs, #9039 and #961, totally valued at more than $532K. He also invested in the Wolf Game, Swampverse, and Sisters collections.  

Jay-Z

Rapper Jay Z owns the Cryptopunk #6095 and one Portrait and one Sneaker from the RTFKT Cryptopunks project. RTFKT Cryptopunks project functions in a similar vein as the 10KFT NFT collection in that it’s only open to punk owners. 10,000 unique sneakers were created via the corresponding punk from the original Cryptopunks project.

Beeple

The artist Beeple is one of the most valuable crypto art creators today. He made the headlines in 2021 after he sold the Everydays: The First 5000 Days collection for $69M in an auction at Christie’s. 

His NFT portfolio, which consists of works other than his own, isn’t modest either. He gave back to the NFT ecosystem by investing more than $400M in various artists on the Rarible platform. Additionally, he’s some pieces from the Veefriends, Cryptocubes, and Meebits collections.

Mark Cuban

Billionaire entrepreneur Mark Cuban also collected a large number of NFT artworks from the Rarible platform. His NFT portfolio is worth around $467M, with BAYC # 1597 and FEWO Crypto Brick being the most precious pieces. The latter is a collaboration between the RTFKT studios and the well-known NFT artist Fewocious.

Other notable celebrity NFT collectors include the NBA star Stephen Curry and the Rapper Ja Rule. The most valuable asset in Curry’s portfolio is the #7990 BAYC. Ja Rule has the #3512 from the Mutant Ape Yacht Club collection.

Final Thoughts: Celebrities Are Loving NFTs

The influx of multifaceted musicians, entrepreneurs, artists, and professional sports players into the NFT space has been welcomed by open arms by all NFT holders. 

Many NFT-holding celebrities tend to acquire pieces from iconic NFT collections such as the BAYC, Cool Cats, and Crypto Punks, but we’re also seeing many celebrities invest in individual artists’ works. In recent months, owning a BAYC or Punk evolved from being something that just crypto people collected to a status symbol for celebrities and athletes. 

We’re eager to follow the celebrity movement into NFTs and explore what’s next on the horizon. 

NFT Copyright: What Artists and Collectors Should Know

NFT art is soaring in popularity due to the blockchain’s ability to offer a multitude of features that appeal to both creators and collectors. 

Artists continue earning royalties for the same artwork from the sales in the secondary market, which isn’t possible in the traditional art scene. 

Collectors enjoy advantages that weren’t possible before blockchain technology, such as an undisputable artwork’s transaction history and provenance, scarcity, and liquidity. 

However, the NFT ownership concept is more complicated than meets the eye, and it often trips up many.

But what do I actually own? 

What if someone just screenshots your art? 

Can I sue someone if they print my NFT on a shirt?

The answer to all of these questions is a nebulous “it depends.”

When someone buys an art NFT, they don’t purchase the artwork itself but the token that represents it. 

Owning the token isn’t necessarily the same thing as owning the copyrights of the underlying asset, unless it was specified in the underlying contract. 

The following guide explores what NFT copyright is, and what both creators and collectors should know about their NFTs. 

Copyrights and intellectual property rights

Copyright is a bundle of rights that specify what’s ok and what isn’t, regarding things like reproducing and distributing copies of the work, preparing derivatives based on the original work, displaying the work in public, and performing the work publicly, as regulated by 17 U.S. Code § 106.

Purchasing an NFT doesn’t transfer these rights to the buyer automatically. Unless an external agreement (17 U.S. Code § 204) is made between the artist and the purchaser,  the artist who created the original artwork remains the copyright holder.

The artist can transfer the copyright, grant a license for specific purposes, or limit the NFT’s use in some way. Agreements used for transferring rights must be coded in the smart contracts or expressed in written terms elsewhere.

Intellectual property (IP) is a broader concept that can refer to any product of the human intellect that the law protects from unauthorized use by others. Patents, copyrights, trademarks, and trade secrets all fall into the realm of IP.

Again, the only way an NFT buyer can retain IP rights is through an explicit agreement signed by the creator of the original artwork.

Standard license agreements for NFT ownership confer the rights to use, copy, display, resale, and gift NFTs. Granting a license of copyright and IP to the buyer through smart contracts or external agreements is also common. Some NFT projects permit commercial use, like CryptoKitties. 

CryptoKitty owners can use them to commercialize their own merchandise, given that they don’t earn more than $100K per year. Another well-known NFT project, Bored Ape Yacht Club, has generous IP terms similar to CryptoKitties. For example, owners are allowed to create characters around their apes or print them on their personal belongings.

Copyright Terms of NFT Marketplaces 

Although there’ll always be exceptions, we can say that in open marketplaces like Opensea and Rarible, artists license the NFTs to the buyer and not to the marketplace.

In marketplaces where only exclusive NFT collections are sold, the marketplace usually owns the NFTs and the related IP rights, like in the case of NBA Top Shot.

Curated marketplaces like Superrare, MakersPlace, and Nifty Gateway, artists are expected to grant licenses for display, distribution, and derivative rights, for promotional activities. Some marketplaces require artists not to mint multiple NFTs for the same artwork.

On Rarible and MakersPlace, artists can apply a custom license to their NFTs, in addition to platforms’ own standard agreements.

When an NFT is resold, the general practice is that any resale activity terminates the former owner’s rights and the current owner of that NFT becomes the new license holder.

NFT Copyright: What You Should Know as a Collector 

As a rule of thumb, NFT owners generally only have the copyrights to resale and gift their NFTs. Please don’t assume you can create derivatives of the underlying artworks and sell them for commercial purposes by default. 

Some projects may be cool with it, others may not. 

Some projects may give holders every possible right under the sun with their NFT, whereas others insist on keeping the project’s branding, and every NFT, held close. 

Always research the related platform’s license terms and conditions yourself if your intentions are beyond reselling the artwork in the secondary market. Otherwise, copyright infringement issues may arise.

It would help if you also bought only on platforms you trust. Always double-check if the artist verifies the related artwork as theirs. In May 2021, artist Xcopy, a famous figure in the crypto art community, tweeted about a fraud regarding his art on a new platform called Hen. 

This isn’t a rare event in the NFT world; always check if you’re buying an original work of art.

NFT Copyright: What you Should Know as an Artist

Artists should only mint their own creations. If the work is done in collaboration with others, their authorization is necessary.

It seems obvious, but in the Wild West vibe of early NFT marketplaces, it seems that you can get away with minting shoddy reproductions of other works. 

Remember how the blockchain tracks every transaction ever? While NFT copyright law is in its wobbly baby deer leg phases now, it’s not difficult to algorithmically track financial and copyright crimes. 

In the NFT world, many frauds take place. If you happen to discover your art is being sold as an NFT by someone else without your consent, you can claim copyright infringement against the sellers.

As stated above, unless you transfer the copyrights to buyers with an external agreement, you hold the copyrights of your work. However, if you did the NFT artwork initially under an employment contract, it might be regarded as work for hire, according to 17 U.S. Code § 101. In this case, the employer might hold the copyrights.

As a precaution against people with bad intentions, you can release your artwork as an NFT before sharing it with someone else.

Finally, like collectors, artists should also be wary of the platform they sell their art and terms and conditions regarding copyrights.  

Final Thoughts: Expect NFT Copyright Law to Evolve

Both collectors and artists should be aware that NFT technology is very new and many issues regarding IP rights are not completely clear. 

Understanding the underlying technology is necessary for both parties, along with the legal aspects. In case of conflicts, consulting lawyers for legal advice is inevitable.