What Is IJK? iShares S&P Mid-Cap 400 Growth ETF

Fast-growing software companies tend not to stay in the mid-cap range for long. The ones that work graduate to large cap, and the ones that do not fall out of the index entirely. What remains in the S&P MidCap 400 growth cohort is a different kind of company: manufacturers, engineering contractors and specialty materials producers whose sales and earnings are accelerating for cyclical or contractual reasons.

The holdings show it plainly. Carpenter Technology and ATI make high-performance alloys for aerospace and defence. Curtiss-Wright supplies engineered components to naval and nuclear programmes. nVent Electric makes electrical enclosures and connections. Sterling Infrastructure and MasTec build things: data centre pads, roads, transmission lines. Woodward makes control systems for aircraft and industrial engines.

That composition means the fund's behaviour is tied to capital spending cycles, defence budgets, grid buildout and construction backlogs, not to software subscription growth. It is a legitimate growth exposure. It is just a different one from what the label implies, and it will not move in step with a large-cap growth fund.

S&P splits its parent indexes into growth and value using multiple factor scores rather than a single ratio. Growth scores draw on measures such as sales growth, earnings change relative to price and momentum. Value scores draw on book value, earnings and sales relative to price. Companies with mixed characteristics can have their market value divided between the growth and value indexes rather than being assigned entirely to one.

That has a practical consequence: IJK and its value counterpart are not mutually exclusive lists. Some companies appear in both, with partial weight in each. Owning both style funds is close to owning the parent MidCap 400, but not identical, because the weighting differs from a straight market cap split.

The top ten holdings sum to roughly 14.2% of the fund, running from 1.6% down to 1.3%. That is a fairly flat distribution, so no single company drives the fund. Compared with large-cap growth funds, where a handful of names can be half the portfolio, this is a far more diffuse structure.

0.17% is reasonable for a style-sliced index fund and roughly three times what the unsliced S&P MidCap 400 costs through the parent fund. The extra is paying for the style screen and the higher turnover that comes from companies moving between the growth and value buckets at each reconstitution.

That raises a fair question about whether the split is worth paying for. If you hold both the growth and value versions, you have approximately reconstructed the parent index at a higher fee and with more internal trading. The split makes sense only if the growth tilt itself is what you want, which is a deliberate choice rather than a default.

The 0.52% yield is low, consistent with a portfolio of companies reinvesting rather than distributing. This is not an income holding. It also means the ongoing tax cost in a taxable account is small, with most of the tax consequence deferred until sale.

Approximate weights as of August 2026. Each ticker links to its individual stock guide in Walnut.

There are three common ways to get IJK exposure. Buy shares (or fractional shares) of IJK directly at any major broker that lists it. Hold it as a core position and layer more concentrated ideas on top. Or build it into a thematic portfolio in Walnut, so IJK sits alongside other holdings that express the same thesis, with target weights you can rebalance toward. IJK trades like a stock during market hours, so you buy it the same way you would any listed share.

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Whether IJK is a good buy depends less on any single call and more on your time horizon and what you already hold: it tracks the S&P MidCap 400 Growth Index, so the real question is whether you want that exposure in your mix and at what weight. We walk through valuation, concentration, and what would have to be true for it to outperform from here in is IJK a buy?

IJK gives you the S&P MidCap 400 Growth Index exposure in one ticker at a 0.17% expense ratio. Most investors use it as a core holding and layer more concentrated thematic portfolios on top.

Whether IJK is worth buying today depends more on your time horizon and what you already hold than on any single call. We walk through valuation, concentration, and what would have to be true for it to outperform from here in is IJK a buy?

IJK yields 0.52% as of August 2026, paid by passing through the dividends of its underlying holdings. For the payout schedule, history, and how the distributions are taxed, see IJK dividend: yield and schedule.

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