Tamil Nadu put up $1 million for the Indus script. Nobody can claim it.

In January 2025, a conference in Chennai marked a hundred years since the world first heard of the Indus civilisation. At that conference, the chief minister of Tamil Nadu offered a million dollars to anyone who could read the Indus script. Twenty months later, nobody has claimed the money.

Many people have tried. Since the 1920s, archaeologists, epigraphists, linguists, engineers, hobbyists and cryptographers have published more than a hundred decipherments. Several were announced as final. The field has accepted none of them. An unclaimed prize is a blunt tool. But it shows the real state of the field better than any press release.

What there is to read

First, the numbers. The numbers are the whole problem.

Researchers have found about four thousand inscribed objects. A 2025 count puts the total nearer five thousand, depending on what you call an inscription. The average inscription is about five signs long. The longest sequence on a single flat surface is on a seal catalogued M-314. It has seventeen signs.

Seventeen signs. That is the longest sentence the Indus civilisation has left us, if it is a sentence at all.

Sometimes you will see the number twenty six instead. That figure comes from a pair of small moulded prisms with three sides. You get it when you add up the signs on all three faces. Is that one text or three? Nobody can answer that question without the ability to read it.

Scholars also disagree about the sign list. Iravatham Mahadevan's 1977 concordance identified 417 distinct signs. That number became the standard, because almost all later computer work used his corpus. Bryan Wells counts closer to 694.

The counts differ for a simple reason. Without a reading, nobody can tell a separate sign from a different style of the same sign. So the list depends on judgement. But the counts agree on the general pattern. About 67 signs make up four fifths of all use. After them comes a long tail of signs that appear once or twice and never again.

And there is nothing else. There is no papyrus, no palm leaf, no birch bark and no wooden tablet. The Harappans possibly wrote on organic materials, but the soil of the Indus plain did not keep them.

The largest inscription in existence is the signboard at Dholavira in Kutch. It has ten signs, each about 37 cm high. The signs are cut from gypsum and were set into a wooden board about three metres long. The board hung over the north gate of the citadel. Then it fell flat on its face. The wood rotted away, and the letters stayed where they landed. R.S. Bisht's team found it in 1991.

Why a century has not been enough

The main difficulty is simple: there is no bilingual text.

Champollion had the Rosetta Stone. It has the same decree written twice, once in Egyptian and once in Greek. Michael Ventris had thousands of Linear B accounting tablets. Eventually he saw that the language under them was an early form of Greek. He could check his work against a language he already knew.

The Indus script has neither advantage. Nobody has ever found a bilingual text. Nobody has identified the language, and it possibly has no living descendants. The script stops around 1900 BCE, and no later script clearly grows out of it.

So anyone who tries must solve three unknowns at once. What are the signs? What language do they write? What do the texts say? Each question alone is hard. Together, they let you produce almost any answer you like. That is exactly why there are over a hundred of them.

The other prize, from the scholars who say there is nothing to read

In 2004, Steve Farmer, Richard Sproat and Michael Witzel published a paper with a very firm title: "The Collapse of the Indus-Script Thesis: The Myth of a Literate Harappan Civilization". They argue that the Indus symbols are not writing at all.

Their case uses the same numbers as everyone else. Real scripts, they say, do not behave like this. The inscriptions are very short, and they stay short across seven centuries of use. A writing system normally does not do that as it develops. Rare signs increase over time instead of dying out, which is again the wrong direction. And the texts lack the untidy, random-looking repetition that spoken language always leaves in writing.

They argue that the symbols look more like a non-linguistic emblem system. Systems of this kind carried religious, political and administrative meaning across the ancient Near East, but they never recorded speech. Their comparison was road and airport signs, and they meant it seriously.

Then they did something unusual for a journal article. They offered $10,000, paid by an anonymous donor and valid for Farmer's lifetime, on one condition:

Turn up just one Indus inscription that contains at least 50 symbols distributed in the outwardly random-appearing ways typical of true scripts contemporary to the Indus system, and we will (1) declare our model to be falsified and (2) will write a check to the discoverer or discoverers for $10,000.

The inscription must come from a known Indus site, and the field must accept it as genuine. The offer has stood for more than twenty years. Nobody has claimed it either.

So two prizes wait on the same pile of evidence. One is for reading it. The other is for proof that there is anything to read at all.

The fight moves to statistics

In 2009, a team led by Rajesh Rao at the University of Washington published a paper in Science. They measured the conditional entropy of Indus sign sequences. This roughly measures how well one sign predicts the next. On that test, the Indus corpus was close to natural languages. It was not close to DNA, protein sequences or Fortran code.

Sproat replied in Computational Linguistics. He called the work "useless" and "trivially and demonstrably wrong". He also made artificial sequences that got similar scores but were not language at all.

Rao answered that this was a strawman. He said he never claimed that entropy alone proved anything. The result was one of several properties that pointed the same way. The exchange continued until 2015 across two journals. Neither side gave an inch.

The exchange produced no reading. It did show that the statistical evidence fits both positions. That result satisfies nobody.

The best argument for a Dravidian reading, and the man who doubted it

The most influential decipherment programme belongs to Asko Parpola. Its most famous piece of evidence is a fish.

The fish sign is common in the corpus. In Old Tamil, min means fish. It also means star, from a root that means to glitter. Possibly the Harappans wrote by rebus, with a picture of one thing for a word that only sounds the same. Then a drawn fish could stand for star.

On seal H-9, seven vertical strokes stand beside a fish. In Old Tamil, elu min, seven stars, is the name for Ursa Major. It is an elegant argument. You can see why it has held people's attention for fifty years.

The complication is the man who doubted it. The whole field depends on Mahadevan's concordance, and he himself believed the language was Dravidian. In a 1994 review of Parpola's book, he wrote that he had doubts about this particular reading.

Later, his settled position was this. The fish signs really do show fish, but they mean something other than stars. Perhaps they use a different Dravidian word for fish, or some wider meaning that we have lost. The Indologist Harry Falk has a blunter objection. The Sumerians, the Akkadians and the Chinese all drew a star as a star. Why would the Harappans not do the same?

Why this is not a quiet academic matter

In India, the question of the Indus language is not a neutral technical question. Was it Dravidian or Indo-Aryan? A Dravidian reading puts the ancestors of the south Indian languages at the centre of the subcontinent's first cities. An Indo-Aryan or Sanskritic reading links the Harappans to the Vedic tradition. People use both readings to settle arguments about who belongs where, and the pressure shows.

In 2000, N.S. Rajaram announced that a Harappan seal showed a horse. That claim would have mattered a lot. Horses are clearly rare in Harappan remains, and they are central to Vedic society.

That October, Witzel and Farmer wrote in Frontline. They showed that the horse was a computer-altered image of a broken unicorn seal. Someone had smoothed over the break and changed the outline of the animal. They published a follow-up the next month. The episode shows how political stakes can distort the evidence.

What we know without the script

Scholars learned almost everything important about the Indus civilisation without reading a single word. People often forget this in the decipherment fights.

We know the seals were stamps, not amulets. When people pressed them into wet clay, they left a sealing that marked a bundle of goods. We know the goods travelled. Indus seals and sealings appear at Ur, at Kish and at Susa. Mesopotamia traded with a place it called Meluhha.

We know that the writing in the impression runs right to left about nine times out of ten. Scholars found this from the signs that get crowded at one end, where the carver ran out of space. We know that a one-horned animal appears on most seals. We also know that a jar-shaped sign is the most common sign of all.

We know the cities had streets in a grid, standard fired bricks and covered drains. Their weight system was very consistent. Small stone cubes from sites hundreds of kilometres apart still match each other. We know there are no clear palaces and no obvious royal tombs. We know the civilisation was at its height for about seven centuries, and then it broke apart.

All of that is archaeology. None of it needed the script. The script would add the one thing that digging cannot give: the Harappans in their own words. It would tell us what they thought was worth carving onto a stamp.

What a million dollars would have to buy

Mahadevan is the right person to end with. He joined the Indian Administrative Service in 1953 and stayed for twenty seven years. In 1970, he took a Nehru Fellowship to work on the script. He published the Concordance in 1977. He continued the work until he died in Chennai in 2018, aged 88. He did more than anyone to make the corpus useful for other people. He never claimed that he had deciphered it.

The government announced the prize together with a two crore rupee chair in his name. It also announced research funding for the Indus Research Centre at the Roja Muthiah Research Library in Chennai.

The prize came after a study by K. Rajan and R. Sivanantham. They digitised more than 15,000 potsherds with graffiti from 140 sites across Tamil Nadu. They reported that over 90 per cent of the marks have parallels among Indus signs.

That study deserves the same doubt as everything else here, and it has received it. The Tamil Nadu megalithic pottery is about a thousand years younger than the mature Harappan script. Falk's objection also stays unanswered: marks scratched on pots were practical marks on pots. They were not necessarily a system for communication. Simple scratches often look alike, and that proves little.

So the prize is back where it started. To win it, somebody must produce a reading that satisfies people who have disagreed with each other for entire careers. The corpus has a longest text of seventeen signs. Nobody has identified the language. There is no bilingual text anywhere. The money looks safe.